what is the symbol used in an assignment statement

• Assignment Statement

An Assignment statement is a statement that is used to set a value to the variable name in a program .

Assignment statement allows a variable to hold different types of values during its program lifespan. Another way of understanding an assignment statement is, it stores a value in the memory location which is denoted by a variable name.

The symbol used in an assignment statement is called as an operator . The symbol is ‘=’ .

Note: The Assignment Operator should never be used for Equality purpose which is double equal sign ‘==’.

The Basic Syntax of Assignment Statement in a programming language is :

variable = expression ;

variable = variable name

expression = it could be either a direct value or a math expression/formula or a function call

Few programming languages such as Java, C, C++ require data type to be specified for the variable, so that it is easy to allocate memory space and store those values during program execution.

data_type variable_name = value ;

In the above-given examples, Variable ‘a’ is assigned a value in the same statement as per its defined data type. A data type is only declared for Variable ‘b’. In the 3 rd line of code, Variable ‘a’ is reassigned the value 25. The 4 th line of code assigns the value for Variable ‘b’.

Assignment Statement Forms

This is one of the most common forms of Assignment Statements. Here the Variable name is defined, initialized, and assigned a value in the same statement. This form is generally used when we want to use the Variable quite a few times and we do not want to change its value very frequently.

Tuple Assignment

Generally, we use this form when we want to define and assign values for more than 1 variable at the same time. This saves time and is an easy method. Note that here every individual variable has a different value assigned to it.

(Code In Python)

Sequence Assignment

(Code in Python)

Multiple-target Assignment or Chain Assignment

In this format, a single value is assigned to two or more variables.

Augmented Assignment

In this format, we use the combination of mathematical expressions and values for the Variable. Other augmented Assignment forms are: &=, -=, **=, etc.

Browse more Topics Under Data Types, Variables and Constants

• Concept of Data types
• Built-in Data Types
• Constants in Programing Language 
• Access Modifier
• Variables of Built-in-Datatypes
• Declaration/Initialization of Variables
• Type Modifier

Few Rules for Assignment Statement

Few Rules to be followed while writing the Assignment Statements are:

• Variable names must begin with a letter, underscore, non-number character. Each language has its own conventions.
• The Data type defined and the variable value must match.
• A variable name once defined can only be used once in the program. You cannot define it again to store other types of value.
• If you assign a new value to an existing variable, it will overwrite the previous value and assign the new value.

FAQs on Assignment Statement

Q1. Which of the following shows the syntax of an  assignment statement ?

• variablename = expression ;
• expression = variable ;
• datatype = variablename ;
• expression = datatype variable ;

Answer – Option A.

Q2. What is an expression ?

• Same as statement
• List of statements that make up a program
• Combination of literals, operators, variables, math formulas used to calculate a value
• Numbers expressed in digits

Answer – Option C.

Q3. What are the two steps that take place when an  assignment statement  is executed?

• Evaluate the expression, store the value in the variable
• Reserve memory, fill it with value
• Evaluate variable, store the result
• Store the value in the variable, evaluate the expression.

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Kenneth Leroy Busbee

An assignment statement sets and/or re-sets the value stored in the storage location(s) denoted by a variable name; in other words, it copies a value into the variable. [1]

The assignment operator allows us to change the value of a modifiable data object (for beginning programmers this typically means a variable). It is associated with the concept of moving a value into the storage location (again usually a variable). Within most programming languages the symbol used for assignment is the equal symbol. But bite your tongue, when you see the = symbol you need to start thinking: assignment. The assignment operator has two operands. The one to the left of the operator is usually an identifier name for a variable. The one to the right of the operator is a value.

Simple Assignment

The value 21 is moved to the memory location for the variable named: age. Another way to say it: age is assigned the value 21.

Assignment with an Expression

The item to the right of the assignment operator is an expression. The expression will be evaluated and the answer is 14. The value 14 would be assigned to the variable named: total_cousins.

Assignment with Identifier Names in the Expression

The expression to the right of the assignment operator contains some identifier names. The program would fetch the values stored in those variables; add them together and get a value of 44; then assign the 44 to the total_students variable.

• cnx.org: Programming Fundamentals – A Modular Structured Approach using C++
• Wikipedia: Assignment (computer science) ↵

Programming Fundamentals Copyright © 2018 by Kenneth Leroy Busbee is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License , except where otherwise noted.

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1.7 Java | Assignment Statements & Expressions

An assignment statement designates a value for a variable. An assignment statement can be used as an expression in Java.

After a variable is declared, you can assign a value to it by using an assignment statement . In Java, the equal sign = is used as the assignment operator . The syntax for assignment statements is as follows:

An expression represents a computation involving values, variables, and operators that, when taking them together, evaluates to a value. For example, consider the following code:

You can use a variable in an expression. A variable can also be used on both sides of the =  operator. For example:

In the above assignment statement, the result of x + 1  is assigned to the variable x . Let’s say that x is 1 before the statement is executed, and so becomes 2 after the statement execution.

To assign a value to a variable, you must place the variable name to the left of the assignment operator. Thus the following statement is wrong:

Note that the math equation  x = 2 * x + 1  ≠ the Java expression x = 2 * x + 1

Which is equivalent to:

And this statement

is equivalent to:

Note: The data type of a variable on the left must be compatible with the data type of a value on the right. For example, int x = 1.0 would be illegal, because the data type of x is int (integer) and does not accept the double value 1.0 without Type Casting .

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Variable Assignment

To "assign" a variable means to symbolically associate a specific piece of information with a name. Any operations that are applied to this "name" (or variable) must hold true for any possible values. The assignment operator is the equals sign which SHOULD NEVER be used for equality, which is the double equals sign.

The '=' symbol is the assignment operator. Warning, while the assignment operator looks like the traditional mathematical equals sign, this is NOT the case. The equals operator is '=='

Design Pattern

To evaluate an assignment statement:

• Evaluate the "right side" of the expression (to the right of the equal sign).
• Once everything is figured out, place the computed value into the variables bucket.

We've already seen many examples of assignment. Assignment means: "storing a value (of a particular type) under a variable name" . Think of each assignment as copying the value of the righthand side of the expression into a "bucket" associated with the left hand side name!

Read this as, the variable called "name" is "assigned" the value computed by the expression to the right of the assignment operator ('=');

Now that you have seen some variables being assigned, tell me what the following code means?

The answer to above questions: the assignment means that lkjasdlfjlskdfjlksjdflkj is a variable (a really badly named one), but a variable none-the-less. jlkajdsf and lkjsdflkjsdf must also be variables. The sum of the two numbers held in jlkajdsf and lkjsdflkjsdf is stored in the variable lkjasdlfjlskdfjlksjdflkj.

Examples of builtin Data and Variables (and Constants)

For more info, use the "help" command: (e.g., help realmin);

Examples of using Data and Variable

Pattern to memorize, assignment pattern.

The assignment pattern creates a new variable, if this is the first time we have seen the "name", or, updates the variable to a new value!

Read the following code in English as: First, compute the value of the thing to the right of the assignment operator (the =). then store the computed value under the given name, destroying anything that was there before.

Or more concisely: assign the variable "name" the value computed by "right_hand_expression"

Assignment Statements

The last thing we discussed in the previous unit were variables. We use variables to store values of an evaluated expression. To store this value, we use an assignment statement . A simple assignment statement consists of a variable name, an equal sign ( assignment operator ) and the value to be stored.

a in the above expression is assigned the value 7.

Here we see that the variable a has 2 added to it's previous value. The resulting number is 9, the addition of 7 and 2.

To break it down into easy steps:

• a = 7 -> Variable is initialized when we store a value in it
• a = a + 2 -> Variable is assigned a new value and forgets the old value

This is called overwriting the variable. a 's value was overwritten in the process. The expression on the right of the = operator is evaluated down to a single value before it is assigned to the variable on the left. During the evaluation stage, a still carries the number 7 , this is added by 2 which results in 9 . 9 is then assigned to the variable a and overwrites the previous value.

Another example:

Hence, when a new value is assigned to a variable, the old one is forgotten.

Variable Names

There are three rules for variable names:

• It can be only one word, no spaces are allowed.
• It can use only letters, numbers, and the underscore (_) character.
• It can’t begin with a number.

Note: Variable names are case-sensitive. This means that hello, Hello, hellO are three different variables. The python convention is to start a variable name with lowercase characters. Tip: A good variable name describes the data it contains. Imagine you have a cat namely Kitty. You could say cat = 'Kitty' .

What would this output: 'name' + 'namename' ? a. 'name' b. 'namenamename' c. 'namename' d. namenamename

What would this output: 'name' * 3 a. 'name' b. 'namenamename' c. 'namename' d. namenamename

results matching " "

No results matching " ".

2. Assignment Statements

One of the most common statements (instructions) in C++ is the assignment statement , which has the form:

= is the assignment operator . This statement means that the expression on the right hand side should be evaluated, and the resulting value stored at the desitnation named on the left. Most often this destination is a variable name, although in come cases the destination is itself arrived at by evaluating an expression to compute where we want to save the value.

Some examples of assignment statements would be

Now, a few things worth noting:

These statements manipulate 4 different variables: pi , r , areaOfCircle and circumferenceOfCircle .

We have to assume that r already contains a sensible value if we are to believe that these assignments will do anythign useful.

The last two only make sense if the first assignment has been performed already. Luckily, when we arrange statements into a straightline arrangement like this, they are performed in that same order.

Note that we have reused pi in two different statements. We didn't need to do this. I could instead have written

but I think the original version is easier to read.

When using variables on either side of an assignment, we need to declare the variables first:

Actually, we can combine the operations of declaring a varable and of assigning its first, or initial value:

Technically these are no longer assignments. Instead they are called initialization statements. But the effect is much the same.

I actually prefer this second, combined version, by the way. One of the more common programming errors is declarign a variable, forgetting to assign it a value, but later trying to use it in a computation anyway. If the variable isn't initialized, you basically get whatever bits happened to be left in memory by the last program that used that address. So you wind up taking an essentially random group of bits, feeding them as input to a calculation, feeding that result into another calculation, and so on, until eventually some poor schmuck gets a telephone bill for $1,245,834 or some piece of expensive computer-controlled machinery tears itself to pieces.

By getting into a habit of always initializing variables while declaring them, I avoid most of the opportunities for ever making this particular mistake.

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CS105: Introduction to Python

Variables and assignment statements.

Computers must be able to remember and store data. This can be accomplished by creating a variable to house a given value. The assignment operator = is used to associate a variable name with a given value. For example, type the command:

in the command line window. This command assigns the value 3.45 to the variable named a . Next, type the command:

in the command window and hit the enter key. You should see the value contained in the variable a echoed to the screen. This variable will remember the value 3.45 until it is assigned a different value. To see this, type these two commands:

You should see the new value contained in the variable a echoed to the screen. The new value has "overwritten" the old value. We must be careful since once an old value has been overwritten, it is no longer remembered. The new value is now what is being remembered.

Although we will not discuss arithmetic operations in detail until the next unit, you can at least be equipped with the syntax for basic operations: + (addition), - (subtraction), * (multiplication), / (division)

For example, entering these command sequentially into the command line window:

would result in 12.32 being echoed to the screen (just as you would expect from a calculator). The syntax for multiplication works similarly. For example:

would result in 35 being echoed to the screen because the variable b has been assigned the value a * 5 where, at the time of execution, the variable a contains a value of 7.

After you read, you should be able to execute simple assignment commands using integer and float values in the command window of the Repl.it IDE. Try typing some more of the examples from this web page to convince yourself that a variable has been assigned a specific value.

In programming, we associate names with values so that we can remember and use them later. Recall Example 1. The repeated computation in that algorithm relied on remembering the intermediate sum and the integer to be added to that sum to get the new sum. In expressing the algorithm, we used th e names current and sum .

In programming, a name that refers to a value in this fashion is called a variable . When we think of values as data stored somewhere i n the computer, we can have a mental image such as the one below for the value 10 stored in the computer and the variable x , which is the name we give to 10. What is most important is to see that there is a binding between x and 10.

The term variable comes from the fact that values that are bound to variables can change throughout computation. Bindings as shown above are created, and changed by assignment statements . An assignment statement associates the name to the left of the symbol = with the value denoted by the expression on the right of =. The binding in the picture is created using an assignment statemen t of the form x = 10 . We usually read such an assignment statement as "10 is assigned to x" or "x is set to 10".

If we want to change the value that x refers to, we can use another assignment statement to do that. Suppose we execute x = 25 in the state where x is bound to 10.Then our image becomes as follows:

Choosing variable names

Suppose that we u sed the variables x and y in place of the variables side and area in the examples above. Now, if we were to compute some other value for the square that depends on the length of the side , such as the perimeter or length of the diagonal, we would have to remember which of x and y , referred to the length of the side because x and y are not as descriptive as side and area . In choosing variable names, we have to keep in mind that programs are read and maintained by human beings, not only executed by machines.

Note about syntax

In Python, variable identifiers can contain uppercase and lowercase letters, digits (provided they don't start with a digit) and the special character _ (underscore). Although it is legal to use uppercase letters in variable identifiers, we typically do not use them by convention. Variable identifiers are also case-sensitive. For example, side and Side are two different variable identifiers.

There is a collection of words, called reserved words (also known as keywords), in Python that have built-in meanings and therefore cannot be used as variable names. For the list of Python's keywords See 2.3.1 of the Python Language Reference.

Syntax and Sema ntic Errors

Now that we know how to write arithmetic expressions and assignment statements in Python, we can pause and think about what Python does if we write something that the Python interpreter cannot interpret. Python informs us about such problems by giving an error message. Broadly speaking there are two categories for Python errors:

• Syntax errors: These occur when we write Python expressions or statements that are not well-formed according to Python's syntax. For example, if we attempt to write an assignment statement such as 13 = age , Python gives a syntax error. This is because Python syntax says that for an assignment statement to be well-formed it must contain a variable on the left hand side (LHS) of the assignment operator "=" and a well-formed expression on the right hand side (RHS), and 13 is not a variable.
• Semantic errors: These occur when the Python interpreter cannot evaluate expressions or execute statements because they cannot be associated with a "meaning" that the interpreter can use. For example, the expression age + 1 is well-formed but it has a meaning only when age is already bound to a value. If we attempt to evaluate this expression before age is bound to some value by a prior assignment then Python gives a semantic error.

Even though we have used numerical expressions in all of our examples so far, assignments are not confined to numerical types. They could involve expressions built from any defined type. Recall the table that summarizes the basic types in Python.

The following video shows execution of assignment statements involving strings. It also introduces some commonly used operators on strings. For more information see the online documentation. In the video below, you see the Python shell displaying "=> None" after the assignment statements. This is unique to the Python shell presented in the video. In most Python programming environments, nothing is displayed after an assignment statement. The difference in behavior stems from version differences between the programming environment used in the video and in the activities, and can be safely ignored.

Distinguishing Expressions and Assignments

So far in the module, we have been careful to keep the distinction between the terms expression and statement because there is a conceptual difference between them, which is sometimes overlooked. Expressions denote values; they are evaluated to yield a value. On the other hand, statements are commands (instructions) that change the state of the computer. You can think of state here as some representation of computer memory and the binding of variables and values in the memory. In a state where the variable side is bound to the integer 3, and the variable area is yet unbound, the value of the expression side + 2 is 5. The assignment statement side = side + 2 , changes the state so that value 5 is bound to side in the new state. Note that when you type an expression in the Python shell, Python evaluates the expression and you get a value in return. On the other hand, if you type an assignment statement nothing is returned. Assignment statements do not return a value. Try, for example, typing x = 100 + 50 . Python adds 100 to 50, gets the value 150, and binds x to 150. However, we only see the prompt >>> after Python does the assignment. We don't see the change in the state until we inspect the value of x , by invoking x .

What we have learned so far can be summarized as using the Python interpreter to manipulate values of some primitive data types such as integers, real numbers, and character strings by evaluating expressions that involve built-in operators on these types. Assignments statements let us name the values that appear in expressions. While what we have learned so far allows us to do some computations conveniently, they are limited in their generality and reusability. Next, we introduce functions as a means to make computations more general and reusable.

• Hands-on Python Tutorial »
• 1. Beginning With Python »

1.6. Variables and Assignment ¶

Each set-off line in this section should be tried in the Shell.

Nothing is displayed by the interpreter after this entry, so it is not clear anything happened. Something has happened. This is an assignment statement , with a variable , width , on the left. A variable is a name for a value. An assignment statement associates a variable name on the left of the equal sign with the value of an expression calculated from the right of the equal sign. Enter

Once a variable is assigned a value, the variable can be used in place of that value. The response to the expression width is the same as if its value had been entered.

The interpreter does not print a value after an assignment statement because the value of the expression on the right is not lost. It can be recovered if you like, by entering the variable name and we did above.

Try each of the following lines:

The equal sign is an unfortunate choice of symbol for assignment, since Python’s usage is not the mathematical usage of the equal sign. If the symbol ↤ had appeared on keyboards in the early 1990’s, it would probably have been used for assignment instead of =, emphasizing the asymmetry of assignment. In mathematics an equation is an assertion that both sides of the equal sign are already, in fact, equal . A Python assignment statement forces the variable on the left hand side to become associated with the value of the expression on the right side. The difference from the mathematical usage can be illustrated. Try:

so this is not equivalent in Python to width = 10 . The left hand side must be a variable, to which the assignment is made. Reversed, we get a syntax error . Try

This is, of course, nonsensical as mathematics, but it makes perfectly good sense as an assignment, with the right-hand side calculated first. Can you figure out the value that is now associated with width? Check by entering

In the assignment statement, the expression on the right is evaluated first . At that point width was associated with its original value 10, so width + 5 had the value of 10 + 5 which is 15. That value was then assigned to the variable on the left ( width again) to give it a new value. We will modify the value of variables in a similar way routinely.

Assignment and variables work equally well with strings. Try:

Try entering:

Note the different form of the error message. The earlier errors in these tutorials were syntax errors: errors in translation of the instruction. In this last case the syntax was legal, so the interpreter went on to execute the instruction. Only then did it find the error described. There are no quotes around fred , so the interpreter assumed fred was an identifier, but the name fred was not defined at the time the line was executed.

It is both easy to forget quotes where you need them for a literal string and to mistakenly put them around a variable name that should not have them!

Try in the Shell :

There fred , without the quotes, makes sense.

There are more subtleties to assignment and the idea of a variable being a “name for” a value, but we will worry about them later, in Issues with Mutable Objects . They do not come up if our variables are just numbers and strings.

Autocompletion: A handy short cut. Idle remembers all the variables you have defined at any moment. This is handy when editing. Without pressing Enter, type into the Shell just

Assuming you are following on the earlier variable entries to the Shell, you should see f autocompleted to be

This is particularly useful if you have long identifiers! You can press Alt-/ several times if more than one identifier starts with the initial sequence of characters you typed. If you press Alt-/ again you should see fred . Backspace and edit so you have fi , and then and press Alt-/ again. You should not see fred this time, since it does not start with fi .

1.6.1. Literals and Identifiers ¶

Expressions like 27 or 'hello' are called literals , coming from the fact that they literally mean exactly what they say. They are distinguished from variables, whose value is not directly determined by their name.

The sequence of characters used to form a variable name (and names for other Python entities later) is called an identifier . It identifies a Python variable or other entity.

There are some restrictions on the character sequence that make up an identifier:

The characters must all be letters, digits, or underscores _ , and must start with a letter. In particular, punctuation and blanks are not allowed.

There are some words that are reserved for special use in Python. You may not use these words as your own identifiers. They are easy to recognize in Idle, because they are automatically colored orange. For the curious, you may read the full list:

There are also identifiers that are automatically defined in Python, and that you could redefine, but you probably should not unless you really know what you are doing! When you start the editor, we will see how Idle uses color to help you know what identifies are predefined.

Python is case sensitive: The identifiers last , LAST , and LaSt are all different. Be sure to be consistent. Using the Alt-/ auto-completion shortcut in Idle helps ensure you are consistent.

What is legal is distinct from what is conventional or good practice or recommended. Meaningful names for variables are important for the humans who are looking at programs, understanding them, and revising them. That sometimes means you would like to use a name that is more than one word long, like price at opening , but blanks are illegal! One poor option is just leaving out the blanks, like priceatopening . Then it may be hard to figure out where words split. Two practical options are

• underscore separated: putting underscores (which are legal) in place of the blanks, like price_at_opening .
• using camel-case : omitting spaces and using all lowercase, except capitalizing all words after the first, like priceAtOpening

Use the choice that fits your taste (or the taste or convention of the people you are working with).

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Variables, Expressions, and Assignments

Variables, expressions, and assignments 1 #, introduction #.

In this chapter, we introduce some of the main building blocks needed to create programs–that is, variables, expressions, and assignments. Programming related variables can be intepret in the same way that we interpret mathematical variables, as elements that store values that can later be changed. Usually, variables and values are used within the so-called expressions. Once again, just as in mathematics, an expression is a construct of values and variables connected with operators that result in a new value. Lastly, an assignment is a language construct know as an statement that assign a value (either as a constant or expression) to a variable. The rest of this notebook will dive into the main concepts that we need to fully understand these three language constructs.

Values and Types #

A value is the basic unit used in a program. It may be, for instance, a number respresenting temperature. It may be a string representing a word. Some values are 42, 42.0, and ‘Hello, Data Scientists!’.

Each value has its own type : 42 is an integer ( int in Python), 42.0 is a floating-point number ( float in Python), and ‘Hello, Data Scientists!’ is a string ( str in Python).

The Python interpreter can tell you the type of a value: the function type takes a value as argument and returns its corresponding type.

Observe the difference between type(42) and type('42') !

Expressions and Statements #

On the one hand, an expression is a combination of values, variables, and operators.

A value all by itself is considered an expression, and so is a variable.

When you type an expression at the prompt, the interpreter evaluates it, which means that it calculates the value of the expression and displays it.

In boxes above, m has the value 27 and m + 25 has the value 52 . m + 25 is said to be an expression.

On the other hand, a statement is an instruction that has an effect, like creating a variable or displaying a value.

The first statement initializes the variable n with the value 17 , this is a so-called assignment statement .

The second statement is a print statement that prints the value of the variable n .

The effect is not always visible. Assigning a value to a variable is not visible, but printing the value of a variable is.

Assignment Statements #

We have already seen that Python allows you to evaluate expressions, for instance 40 + 2 . It is very convenient if we are able to store the calculated value in some variable for future use. The latter can be done via an assignment statement. An assignment statement creates a new variable with a given name and assigns it a value.

The example in the previous code contains three assignments. The first one assigns the value of the expression 40 + 2 to a new variable called magicnumber ; the second one assigns the value of π to the variable pi , and; the last assignment assigns the string value 'Data is eatig the world' to the variable message .

Programmers generally choose names for their variables that are meaningful. In this way, they document what the variable is used for.

Do It Yourself!

Let’s compute the volume of a cube with side \(s = 5\) . Remember that the volume of a cube is defined as \(v = s^3\) . Assign the value to a variable called volume .

Well done! Now, why don’t you print the result in a message? It can say something like “The volume of the cube with side 5 is \(volume\) ”.

Beware that there is no checking of types ( type checking ) in Python, so a variable to which you have assigned an integer may be re-used as a float, even if we provide type-hints .

Names and Keywords #

Names of variable and other language constructs such as functions (we will cover this topic later), should be meaningful and reflect the purpose of the construct.

In general, Python names should adhere to the following rules:

It should start with a letter or underscore.

It cannot start with a number.

It must only contain alpha-numeric (i.e., letters a-z A-Z and digits 0-9) characters and underscores.

They cannot share the name of a Python keyword.

If you use illegal variable names you will get a syntax error.

By choosing the right variables names you make the code self-documenting, what is better the variable v or velocity ?

The following are examples of invalid variable names.

These basic development principles are sometimes called architectural rules . By defining and agreeing upon architectural rules you make it easier for you and your fellow developers to understand and modify your code.

If you want to read more on this, please have a look at Code complete a book by Steven McConnell [ McC04 ] .

Every programming language has a collection of reserved keywords . They are used in predefined language constructs, such as loops and conditionals . These language concepts and their usage will be explained later.

The interpreter uses keywords to recognize these language constructs in a program. Python 3 has the following keywords:

False class finally is return

None continue for lambda try

True def from nonlocal while

and del global not with

as elif if or yield

assert else import pass break

except in raise

Reassignments #

It is allowed to assign a new value to an existing variable. This process is called reassignment . As soon as you assign a value to a variable, the old value is lost.

The assignment of a variable to another variable, for instance b = a does not imply that if a is reassigned then b changes as well.

You have a variable salary that shows the weekly salary of an employee. However, you want to compute the monthly salary. Can you reassign the value to the salary variable according to the instruction?

Updating Variables #

A frequently used reassignment is for updating puposes: the value of a variable depends on the previous value of the variable.

This statement expresses “get the current value of x , add one, and then update x with the new value.”

Beware, that the variable should be initialized first, usually with a simple assignment.

Do you remember the salary excercise of the previous section (cf. 13. Reassignments)? Well, if you have not done it yet, update the salary variable by using its previous value.

Updating a variable by adding 1 is called an increment ; subtracting 1 is called a decrement . A shorthand way of doing is using += and -= , which stands for x = x + ... and x = x - ... respectively.

Order of Operations #

Expressions may contain multiple operators. The order of evaluation depends on the priorities of the operators also known as rules of precedence .

For mathematical operators, Python follows mathematical convention. The acronym PEMDAS is a useful way to remember the rules:

Parentheses have the highest precedence and can be used to force an expression to evaluate in the order you want. Since expressions in parentheses are evaluated first, 2 * (3 - 1) is 4 , and (1 + 1)**(5 - 2) is 8 . You can also use parentheses to make an expression easier to read, even if it does not change the result.

Exponentiation has the next highest precedence, so 1 + 2**3 is 9 , not 27 , and 2 * 3**2 is 18 , not 36 .

Multiplication and division have higher precedence than addition and subtraction . So 2 * 3 - 1 is 5 , not 4 , and 6 + 4 / 2 is 8 , not 5 .

Operators with the same precedence are evaluated from left to right (except exponentiation). So in the expression degrees / 2 * pi , the division happens first and the result is multiplied by pi . To divide by 2π, you can use parentheses or write: degrees / 2 / pi .

In case of doubt, use parentheses!

Let’s see what happens when we evaluate the following expressions. Just run the cell to check the resulting value.

Floor Division and Modulus Operators #

The floor division operator // divides two numbers and rounds down to an integer.

For example, suppose that driving to the south of France takes 555 minutes. You might want to know how long that is in hours.

Conventional division returns a floating-point number.

Hours are normally not represented with decimal points. Floor division returns the integer number of hours, dropping the fraction part.

You spend around 225 minutes every week on programming activities. You want to know around how many hours you invest to this activity during a month. Use the \(//\) operator to give the answer.

The modulus operator % works on integer values. It computes the remainder when dividing the first integer by the second one.

The modulus operator is more useful than it seems.

For example, you can check whether one number is divisible by another—if x % y is zero, then x is divisible by y .

String Operations #

In general, you cannot perform mathematical operations on strings, even if the strings look like numbers, so the following operations are illegal: '2'-'1' 'eggs'/'easy' 'third'*'a charm'

But there are two exceptions, + and * .

The + operator performs string concatenation, which means it joins the strings by linking them end-to-end.

The * operator also works on strings; it performs repetition.

Speedy Gonzales is a cartoon known to be the fastest mouse in all Mexico . He is also famous for saying “Arriba Arriba Andale Arriba Arriba Yepa”. Can you use the following variables, namely arriba , andale and yepa to print the mentioned expression? Don’t forget to use the string operators.

Asking the User for Input #

The programs we have written so far accept no input from the user.

To get data from the user through the Python prompt, we can use the built-in function input .

When input is called your whole program stops and waits for the user to enter the required data. Once the user types the value and presses Return or Enter , the function returns the input value as a string and the program continues with its execution.

Try it out!

You can also print a message to clarify the purpose of the required input as follows.

The resulting string can later be translated to a different type, like an integer or a float. To do so, you use the functions int and float , respectively. But be careful, the user might introduce a value that cannot be converted to the type you required.

We want to know the name of a user so we can display a welcome message in our program. The message should say something like “Hello \(name\) , welcome to our hello world program!”.

Script Mode #

So far we have run Python in interactive mode in these Jupyter notebooks, which means that you interact directly with the interpreter in the code cells . The interactive mode is a good way to get started, but if you are working with more than a few lines of code, it can be clumsy. The alternative is to save code in a file called a script and then run the interpreter in script mode to execute the script. By convention, Python scripts have names that end with .py .

Use the PyCharm icon in Anaconda Navigator to create and execute stand-alone Python scripts. Later in the course, you will have to work with Python projects for the assignments, in order to get acquainted with another way of interacing with Python code.

This Jupyter Notebook is based on Chapter 2 of the books Python for Everybody [ Sev16 ] and Think Python (Sections 5.1, 7.1, 7.2, and 5.12) [ Dow15 ] .

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2.3: Arithmetic Operations and Assignment Statements

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• Page ID 206261

• Robert Belford
• University of Arkansas at Little Rock

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hypothes.is tag:  s20iostpy03ualr Download Assignment:  S2020py03

Learning Objectives

Students will be able to:

• Explain each Python arithmetic operator
• Explain the meaning and use of an  assignment statement
• Explain the use of "+"  and "*" with strings and numbers
• Use the  int()   and  float()  functions to convert string input to numbers for computation
• Incorporate numeric formatting into print statements
• Recognize the four main operations of a computer within a simple Python program
• Create  input  statements in Python
• Create  Python  code that performs mathematical and string operations
• Create  Python  code that uses assignment statements
• Create  Python   code that formats numeric output

Prior Knowledge

• Understanding of Python print and input statements
• Understanding of mathematical operations
• Understanding of flowchart input symbols

Further Reading

• https://en.wikibooks.org/wiki/Non-Programmer%27s_Tutorial_for_Python_3/Hello,_World
• https://en.wikibooks.org/wiki/Non-Programmer%27s_Tutorial_for_Python_3/Who_Goes_There%3F

Model 1: Arithmetic Operators in  Python

Python includes several arithmetic operators: addition, subtraction, multiplication, two types of division, exponentiation and  mod .

Critical Thinking Questions:

1.  Draw a line between each flowchart symbol and its corresponding line of Python code. Make note of any problems.

2. Execute the print statements in the previous Python program

    a.  Next to each print statement above, write the output.     b.  What is the value of the following line of code?

    c.  Predict the values of 17%3 and 18%3 without using your computer.

3.  Explain the purpose of each arithmetic operation:

a.               +          ____________________________

b.               -           ____________________________

c.               *          ____________________________

d.               **        ____________________________

e.               /           ____________________________

f.                //          ____________________________

g.                %         ____________________________

An  assignment statement  is a line of code that uses a "=" sign. The statement stores the result of an operation performed on the right-hand side of the sign into the variable memory location on the left-hand side.

4.         Enter and execute the following lines of Python code in the editor window of your IDE (e.g. Thonny):

 a.  What are the variables in the above python program?    b.  What does the  assignment statement :  MethaneMolMs = 16  do?    c.  What happens if you replace the comma (,) in the print statements with a plus sign (+) and execute the code again?  Why does this happen?

5.    What is stored in memory after each assignment statement is executed?

Note: Concatenating Strings in python

The "+"  concatenates  the two strings stored in the variables into one string.    "+" can only be used when both operators are strings.

6.         Run the following program in the editor window of your IDE (e.g. Thonny) to see what happens if you try to use the "+" with strings instead of numbers?

   a.  The third line of code contains an assignment statement. What is stored in  fullName   when the line is executed?    b.  What is the difference between the two output lines?    c.  How could you alter your assignment statements so that  print(fullName)  gives the same output as  print(firstName,lastName)    d. Only one of the following programs will work. Which one will work, and why doesn’t the other work? Try doing this without running the programs!

   e.  Run the programs above and see if you were correct.    f.  The program that worked above results in no space between the number and the street name. How can you alter the code so that it prints properly while using a concatenation operator?

7.  Before entering the following code into the Python interpreter (Thonny IDE editor window), predict the output of this program.

Now execute it.  What is the actual output?  Is this what you thought it would do?  Explain.

8.   Let’s take a look at a python program that prompts the user for two numbers and subtracts them. 

            Execute the following code by entering it in the editor window of Thonny.

      a.   What output do you expect?       b.   What is the actual output       c.   Revise the program in the following manner:

• Between lines two and three add the following lines of code:       num1 = int(firstNumber)      num2 = int(secondNumber)
• Next, replace the statement:     difference = firstNumber – secondNumber with the statement:     difference = num1 – num2
• Execute the program again. What output did you get?

     d.  Explain the purpose of the function  int().      e.  Explain how the changes in the program produced the desired output.

Model 3: Formatting Output in  Python

There are multiple ways to format output in python. The old way is to use the string modulo %, and the new way is with a format method function.

9.  Look closely at the output for python program 7.

    a. How do you indicate the number of decimals to display using

the string modulo (%) ______________________________________________________

the format function ________________________________________________________

     b. What happens to the number if you tell it to display less decimals than are in the number, regardless of formatting method used?

     c. What type of code allows you to right justify your numbers?

10.       Execute the following code by entering it in the editor window of Thonny.

a.  Does the output look like standard output for something that has dollars and cents associated with it?

b.  Replace the last line of code with the following:

print("Total cost of laptops: $%.2f" % price)   

print("Total cost of laptops:" ,format(price, '.2f.))

                Discuss the change in the output.

c.  Replace the last line of code with the following:

print("Total cost of laptops: $",   format(price,'.2f') print("Total cost of laptops: $" ,format(price, '.2f.))

              Discuss the change in the output.

d.  Experiment with the number ".2" in the ‘0.2f’ of the print above statement by substituting the following numbers and explain the results.

                     .4         ___________________________________________________

                     .0         ___________________________________________________

                     .1         ___________________________________________________

                     .8         ___________________________________________________

e.  Now try the following numbers in the same print statement. These numbers contain a whole number and a decimal. Explain the output for each number.

                     02.5     ___________________________________________________

                     08.2     ___________________________________________________

                     03.1     ___________________________________________________

f.  Explain what each part of the format function:  format(variable,  "%n.nf")  does in a print statement where n.n represents a number.

variable ____________________________           First n _________________________

Second n_______________________                      f    _________________________

g.          Revise the print statement by changing the "f" to "d" and  laptopCost = 600 . Execute the statements and explain the output format.

            print("Total cost of laptops: %2d" % price)             print("Total cost of laptops: %10d" % price)

h.         Explain how the function  format(var,'10d')  formats numeric data.  var  represents a whole number.

11.    Use the following program and output to answer the questions below.

a.   From the code and comments in the previous program, explain how the four main operations are implemented in this program. b.  There is one new function in this sample program.  What is it? From the corresponding output, determine what it does.

Application Questions: Use the Python Interpreter to check your work

• 8 to the 4 th  power
• The sum of 5 and 6 multiplied by the quotient of 34 and 7 using floating point arithmetic  
• Write an assignment statement that stores the remainder obtained from dividing 87 and 8 in the variable  leftover  
• Assume:  

courseLabel = "CHEM" courseNumber = "3350"

Write a line of Python code that concatenates the label with the number and stores the result in the variable  courseName . Be sure that there is a space between the course label and the course number when they are concatenated.

• Write one line of Python code that will print the word "Happy!" one hundred times.  
• Write one line of code that calculates the cost of 15 items and stores the result in the variable  totalCost
• Write one line of code that prints the total cost with a label, a dollar sign, and exactly two decimal places.  Sample output:  Total cost: $22.5  
• Assume: 

height1 = 67850 height2 = 456

Use Python formatting to write two print statements that will produce the following output exactly at it appears below:

Homework Assignment: s2020py03

Download the assignment from the website, fill out the word document, and upload to your Google Drive folder the completed assignment along with the two python files.

1. (5 pts)  Write a Python program that prompts the user for two numbers, and then gives the sum and product of those two numbers. Your sample output should look like this:

Enter your first number:10 Enter your second number:2 The sum of these numbers is: 12 The product of these two numbers is: 20

• Your program must contain documentation lines that include your name, the date, a line that states "Py03 Homework question 1" and a description line that indicates what the program is supposed to do. 
• Paste the code this word document and upload to your Google drive when the assignment is completed, with file name [your last name]_py03_HWQ1
• Save the program as a python file (ends with .py), with file name [your last name]_py03Q1_program and upload that to the Google Drive.

2. (10 pts) Write a program that calculates the molarity of a solution. Molarity is defined as numbers of moles per liter solvent. Your program will calculate molarity and must ask for the substance name, its molecular weight, how many grams of substance you are putting in solution, and the total volume of the solution. Report your calculated value of molarity to 3 decimal places. Your output should also be separated from the input with a line containing 80 asterixis.

Assuming you are using sodium chloride, your input and output should look like:

• Your program must contain documentation lines that include your name, the date, a line that states "Py03 Homework question 2" and a description line that indicates what the program is supposed to do. 
• Paste the code to question two below
• Save the program as a python file (ends with .py), with file name [your last name]_py03Q2_program and upload that to the Google Drive.

3. (4 pts) Make two hypothes.is annotations dealing with external open access resources on formatting with the format function method of formatting.  These need the tag of s20iostpy03ualr .

Copyright Statement

26 Types of Punctuation Marks & Typographical Symbols

• What Is Punctuation?
• What Is A Typographical Symbol?
• Punctuation Vs. Typographical Symbols
• Types Of Punctuation And Symbols
• Try Grammar Coach

We use words in writing. Shocking, I know! Do you know what else we use in writing? Here is a hint: they have already appeared in this paragraph. In addition to words, we use many different symbols and characters to organize our thoughts and make text easier to read. All of these symbols come in two major categories: punctuation marks and typographical symbols . These symbols have many different uses and include everything from the humble period ( . ) to the rarely used caret symbol ( ^ ). There may even be a few symbols out there that you’ve never even heard of before that leave you scratching your head when you see them on your keyboard!

What is punctuation ?

Punctuation is the act or system of using specific marks or symbols in writing to separate different elements from each other or to make writing more clear. Punctuation is used in English and the other languages that use the Latin alphabet. Many other writing systems also use punctuation, too. Thanks to punctuation, we don’t have to suffer through a block of text that looks like this:

• My favorite color is red do you like red red is great my sister likes green she always says green is the color of champions regardless of which color is better we both agree that no one likes salmon which is a fish and not a color seriously

Punctuation examples

The following sentences give examples of the many different punctuation marks that we use:

• My dog , Bark Scruffalo , was featured in a superhero movie . 
• If there ’ s something strange in your neighborhood , who are you going to call ?
• A wise man once said , “ Within the body of every person lies a skeleton .”
• Hooray ! I found everything on the map : the lake , the mountain , and the forest . 
• I told Ashley ( if that was her real name ) that I needed the copy lickety-split .

What is a typographical symbol ?

The term typographical symbol , or any other number of phrases, refers to a character or symbol that isn’t considered to be a punctuation mark but may still be used in writing for various purposes. Typographical symbols are generally avoided in formal writing under most circumstances. However, you may see typographic symbols used quite a bit in informal writing.

Typographical symbol examples

The following examples show some ways that a writer might use typographical symbols. Keep in mind that some of these sentences may not be considered appropriate in formal writing.

• The frustrated actor said she was tired of her co-star’s “annoying bull **** .”
• For questions, email us at anascabana @ bananacabanas.fake!
• The band had five # 1 singles on the American music charts during the 1990s.
• My internet provider is AT & T.

⚡️ Punctuation vs. typographical symbols

Punctuation marks are considered part of grammar and often have well-established rules for how to use them properly. For example, the rules of proper grammar state that a letter after a period should be capitalized and that a comma must be used before a coordinating conjunction.

Typographical symbols, on the other hand, may not have widely accepted rules for how, or even when, they should be used. Generally speaking, most grammar resources will only allow the use of typographical symbols under very specific circumstances and will otherwise advise a writer to avoid using them.

Types of punctuation and symbols

There are many different types of punctuation marks and typographical symbols. We’ll briefly touch on them now, but you can learn more about these characters by checking out the links in this list and also each section below:

• Question mark
• Exclamation point
• Parentheses
• Square brackets
• Curly brackets
• Angle brackets
• Quotation marks
• Bullet point
• Pound symbol
• Caret symbol
• Pipe symbol

Period, question mark, and exclamation point

These three commonly used punctuation marks are used for the same reason: to end an independent thought.

A period is used to end a declarative sentence . A period indicates that a sentence is finished.

• Today is Friday .

Unique to them, periods are also often used in abbreviations.

• Prof . Dumbledore once again awarded a ludicrous amount of points to Gryffindor.

Question mark (?)

The question mark is used to end a question, also known as an interrogative sentence .

• Do you feel lucky ?

Exclamation point (!)

The exclamation point is used at the end of exclamations and interjections .

• Our house is haunted ! 

Comma, colon, and semicolon

Commas, colons, and semicolons can all be used to connect sentences together.

The comma is often the punctuation mark that gives writers the most problems. It has many different uses and often requires good knowledge of grammar to avoid making mistakes when using it. Some common uses of the comma include:

• Joining clauses: Mario loves Peach , and she loves him . 
• Nonrestrictive elements: My favorite team , the Fighting Mongooses , won the championship this year.
• Lists: The flag was red , white , and blue.
• Coordinate adjectives: The cute , happy puppy licked my hand.

Try out this quiz on the Oxford comma!

The colon is typically used to introduce additional information.

• The detective had three suspects : the salesman, the gardener, and the lawyer.

Like commas, colons can also connect clauses together.

• We forgot to ask the most important question : who was buying lunch?

Colons have a few other uses, too.

• The meeting starts at 8:15 p.m.
• The priest started reading from Mark 3:6 .

Semicolon (;)

Like the comma and the colon, the semicolon is used to connect sentences together. The semicolon typically indicates that the second sentence is closely related to the one before it.

• I can’t eat peanuts ; I am highly allergic to them.
• Lucy loves to eat all kinds of sweets ; lollipops are her favorite.

Hyphen and dashes (en dash and em dash)

All three of these punctuation marks are often referred to as “dashes.” However, they are all used for entirely different reasons.

The hyphen is used to form compound words.

• I went to lunch with my father-in-law .
• She was playing with a jack-in-the-box .
• He was accused of having pro-British sympathies.

En dash (–)

The en dash is used to express ranges or is sometimes used in more complex compound words.

• The homework exercises are on pages 20–27 .
• The songwriter had worked on many Tony Award–winning productions.

Em dash (—)

The em dash is used to indicate a pause or interrupted speech.

• The thief was someone nobody expected —me !
• “Those kids will— ” was all he managed to say before he was hit by a water balloon.

Test your knowledge on the different dashes here.

Parentheses, brackets, and braces

These pairs of punctuation marks look similar, but they all have different uses. In general, the parentheses are much more commonly used than the others.

Parentheses ()

Typically, parentheses are used to add additional information.

• I thought (for a very long time) if I should actually give an honest answer.
• Tomorrow is Christmas (my favorite holiday) !

Parentheses have a variety of other uses, too.

• Pollution increased significantly. (See Chart 14B)
• He was at an Alcoholics Anonymous (AA) meeting.
• Richard I of England (1157–1199) had the heart of a lion.

Square brackets []

Typically, square brackets  are used to clarify or add information to quotations.

• According to an eyewitness, the chimpanzees “climbed on the roof and juggled [bananas] .”
• The judge said that “the defense attorney [Mr. Wright] had made it clear that the case was far from closed.”

Curly brackets {}

Curly brackets , also known as braces , are rarely used punctuation marks that are used to group a set.

• I was impressed by the many different colors {red, green, yellow, blue, purple, black, white} they selected for the flag’s design.

Angle brackets <>

Angle brackets have no usage in formal writing and are rarely ever used even in informal writing. These characters have more uses in other fields, such as math or computing.

Quotation marks and apostrophe

You’ll find these punctuation marks hanging out at the top of a line of text.

Quotation marks (“”)

The most common use of quotation marks is to contain quotations.

• She said, “ Don’t let the dog out of the house. ”
• Bob Ross liked to put “ happy little trees ” in many of his paintings.

Apostrophe (‘)

The apostrophe is most often used to form possessives and contractions.

• The house ’ s back door is open.
• My cousin ’ s birthday is next week.
• It isn ’ t ready yet.
• We should ’ ve stayed outside.

Slash and ellipses

These are two punctuation marks you may not see too often, but they are still useful.

The slash has several different uses. Here are some examples:

• Relationships: The existence of boxer briefs somehow hasn’t ended the boxers/briefs debate.
• Alternatives: They accept cash and/or credit.
• Fractions: After an hour, 2/3 of the audience had already left.

Ellipses (…)

In formal writing, ellipses are used to indicate that words were removed from a quote.

• The mayor said, “The damages will be … paid for by the city … as soon as possible.”

In informal writing, ellipses are often used to indicate pauses or speech that trails off.

• He nervously stammered and said, “Look, I … You see … I wasn’t … Forget it, okay.”

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Typographical symbols

Typographical symbols rarely appear in formal writing. You are much more likely to see them used for a variety of reasons in informal writing.

Asterisk (*)

In formal writing, especially academic and scientific writing, the asterisk is used to indicate a footnote.

• Chocolate is the preferred flavor of ice cream.* * According to survey data from the Ice Cream Data Center.

The asterisk may also be used to direct a reader toward a clarification or may be used to censor inappropriate words or phrases.

Ampersand (&)

The ampersand substitutes for the word and . Besides its use in the official names of things, the ampersand is typically avoided in formal writing.

•  The band gave a speech at the Rock & Roll Hall of Fame .

Bullet Point (•)

Bullet points are used to create lists. For example,

For this recipe you will need:

• baking powder

Pound symbol (#)

Informally, the pound symbol is typically used to mean number or is used in social media hashtags.

• The catchy pop song reached #1 on the charts.
• Ready 4 Halloween 2morrow!!! #spooky #TrickorTreat

Besides being used as an accent mark in Spanish and Portuguese words, the tilde is rarely used. Informally, a person may use it to mean “about” or “approximately.”

• We visited São Paulo during our vacation.
• I think my dog weighs ~20 pounds.

Backslash (\)

The backslash is primarily used in computer programming and coding. It might be used online and in texting to draw emoticons , but it has no other common uses in writing. Be careful not to mix it up with the similar forward slash (/), which is a punctuation mark.

At symbol (@)

The at symbol substitutes for the word at in informal writing. In formal writing, it is used when writing email addresses.

• His email address is [email protected] .

Caret symbol (^)

The caret symbol is used in proofreading, but may be used to indicate an exponent if a writer is unable to use superscript .

• Do you know what 3 ^ 4 (3 to the power of 4) is equal to?

Pipe symbol (|)

The pipe symbol is not used in writing. Instead, it has a variety of functions in the fields of math, physics, or computing.

How much do you know about verbs? Learn about them here.

Ways To Say

Synonym of the day

Mac keyboard shortcuts

By pressing certain key combinations, you can do things that normally need a mouse, trackpad, or other input device.

Using keyboard shortcuts

Common shorcuts like cut, copy, paste

Sleep, log out, and shut down shortcuts

Finder and system shortcuts, document shortcuts, accessibility shortcuts, other shortcuts.

To use a keyboard shortcut, press and hold one or more modifier keys and then press the last key of the shortcut. For example, to use Command-C (copy), press and hold the Command key, then the C key, then release both keys. Mac menus and keyboards often use symbols for certain keys , including modifier keys:

Command (or Cmd) ⌘

Option (or Alt) ⌥

Control (or Ctrl) ⌃

Caps Lock ⇪

On keyboards made for Windows PCs, use the Alt key instead of Option, and the Ctrl key or Windows logo key instead of Command.

Cut, copy, paste, and other common shortcuts

Command-X : Cut the selected item and copy it to the Clipboard.

Command-C : Copy the selected item to the Clipboard. This also works for files in the Finder.

Command-V : Paste the contents of the Clipboard into the current document or app. This also works for files in the Finder.

Command-Z : Undo the previous command. You can then press Shift-Command-Z to Redo, reversing the undo command. In some apps, you can undo and redo multiple commands.

Command-A : Select All items.

Command-F : Find items in a document or open a Find window.

Command-G : Find Again: Find the next occurrence of the item previously found. To find the previous occurrence, press Shift-Command-G.

Command-H : Hide the windows of the front app. To view the front app but hide all other apps, press Option-Command-H.

Command-M : Minimize the front window to the Dock. To minimize all windows of the front app, press Option-Command-M.

Command-O: Open the selected item, or open a dialog to select a file to open.

Command-P : Print the current document.

Command-S : Save the current document.

Command-T : Open a new tab.

Command-W : Close the front window. To close all windows of the app, press Option-Command-W.

Option-Command-Esc : Force quit an app.

Command–Space bar : Show or hide the Spotlight search field. To perform a Spotlight search from a Finder window, press Command–Option–Space bar. (If you use multiple input sources to type in different languages, these shortcuts change input sources instead of showing Spotlight. Learn how to change a conflicting keyboard shortcut .)

Control–Command–Space bar : Show the Character Viewer, from which you can choose emoji and other symbols .

Control-Command-F : Use the app in full screen, if supported by the app.

Space bar : Use Quick Look to preview the selected item.

Command-Tab : Switch to the next most recently used app among your open apps.

Command–Grave accent (`): Switch between the windows of the app you're using. (The character on the second key varies by keyboard. It's generally the key above the Tab key and to the left of the number 1.)

Shift-Command-5 : In macOS Mojave or later , take a screenshot or make a screen recording. Or use Shift-Command-3 or Shift-Command-4 for screenshots. Learn more about screenshots .

Shift-Command-N: Create a new folder in the Finder.

Command-Comma (,) : Open preferences for the front app.

You might need to press and hold some of these shortcuts for slightly longer than other shortcuts. This helps you to avoid using them unintentionally.

Power button : Press to turn on your Mac or wake it from sleep. Press and hold for 1.5 seconds to put your Mac to sleep.* Continue holding to force your Mac to turn off.

Control–Command–Power button :* Force your Mac to restart, without prompting to save any open and unsaved documents.

Control-Command-Q : Immediately lock your screen.

Shift-Command-Q : Log out of your macOS user account. You will be asked to confirm. To log out immediately without confirming, press Option-Shift-Command-Q.

* Does not apply to the Touch ID sensor .

Command-D : Duplicate the selected files.

Command-E : Eject the selected disk or volume.

Command-F : Start a Spotlight search in the Finder window.

Command-I : Show the Get Info window for a selected file.

Command-R : (1) When an alias is selected in the Finder: show the original file for the selected alias. (2) In some apps, such as Calendar or Safari, refresh or reload the page. (3) In Software Update, check for software updates again.

Shift-Command-C : Open the Computer window.

Shift-Command-D : Open the desktop folder.

Shift-Command-F : Open the Recents window, showing all of the files you viewed or changed recently.

Shift-Command-G : Open a Go to Folder window.

Shift-Command-H : Open the Home folder of the current macOS user account.

Shift-Command-I : Open iCloud Drive.

Shift-Command-K : Open the Network window.

Option-Command-L : Open the Downloads folder.

Shift-Command-N: Create a new folder.

Shift-Command-O : Open the Documents folder.

Shift-Command-P : Show or hide the Preview pane in Finder windows.

Shift-Command-R : Open the AirDrop window.

Shift-Command-T : Show or hide the tab bar in Finder windows.

Control-Shift-Command-T : Add selected Finder item to the Dock (OS X Mavericks or later)

Shift-Command-U : Open the Utilities folder.

Option-Command-D : Show or hide the Dock.

Control-Command-T : Add the selected item to the sidebar (OS X Mavericks or later).

Option-Command-P : Hide or show the path bar in Finder windows.

Option-Command-S : Hide or show the Sidebar in Finder windows.

Command–Slash (/) : Hide or show the status bar in Finder windows.

Command-J : Show View Options.

Command-K : Open the Connect to Server window.

Control-Command-A : Make an alias of the selected item.

Command-N : Open a new Finder window.

Option-Command-N : Create a new Smart Folder.

Command-T : Show or hide the tab bar when a single tab is open in the current Finder window.

Option-Command-T : Show or hide the toolbar when a single tab is open in the current Finder window.

Option-Command-V : Move the files in the Clipboard from their original location to the current location.

Command-Y : Use Quick Look to preview the selected files.

Option-Command-Y : View a Quick Look slideshow of the selected files.

Command-1 : View the items in the Finder window as icons.

Command-2 : View the items in a Finder window as a list.

Command-3 : View the items in a Finder window in columns.

Command-4 : View the items in a Finder window in a gallery.

Command–Left Bracket ([) : Go to the previous folder.

Command–Right Bracket (]) : Go to the next folder.

Command–Up Arrow : Open the folder that contains the current folder.

Command–Control–Up Arrow : Open the folder that contains the current folder in a new window.

Command–Down Arrow : Open the selected item.

Right Arrow : Open the selected folder. This works only when in list view.

Left Arrow : Close the selected folder. This works only when in list view.

Command-Delete : Move the selected item to the Trash.

Shift-Command-Delete : Empty the Trash.

Option-Shift-Command-Delete : Empty the Trash without confirmation dialog.

Command–Brightness Down : Turn video mirroring on or off when your Mac is connected to more than one display.

Option–Brightness Up : Open Displays preferences. This works with either Brightness key.

Control–Brightness Up or Control–Brightness Down : Change the brightness of your external display, if supported by your display.

Option–Shift–Brightness Up or Option–Shift–Brightness Down : Adjust the display brightness in smaller steps. Add the Control key to this shortcut to make the adjustment on your external display, if supported by your display.

Option–Mission Control : Open Mission Control preferences.

Command–Mission Control : Show the desktop.

Control–Down Arrow : Show all windows of the front app.

Option–Volume Up : Open Sound preferences. This works with any of the volume keys.

Option–Shift–Volume Up or Option–Shift–Volume Down : Adjust the sound volume in smaller steps.

Option–Keyboard Brightness Up : Open Keyboard preferences. This works with either Keyboard Brightness key.

Option–Shift–Keyboard Brightness Up or Option–Shift–Keyboard Brightness Down : Adjust the keyboard brightness in smaller steps.

Option key while double-clicking : Open the item in a separate window, then close the original window.

Command key while double-clicking : Open a folder in a separate tab or window.

Command key while dragging to another volume : Move the dragged item to the other volume, instead of copying it.

Option key while dragging : Copy the dragged item. The pointer changes while you drag the item.

Option-Command while dragging : Make an alias of the dragged item. The pointer changes while you drag the item.

Option-click a disclosure triangle : Open all folders within the selected folder. This works only when in list view.

Command-click a window title : See the folders that contain the current folder.

Learn how to use Command or Shift to select multiple items in the Finder .

Click the Go menu in the Finder menu bar to see shortcuts for opening many commonly used folders, such as Applications, Documents, Downloads, Utilities, and iCloud Drive.

The behavior of these shortcuts may vary with the app you're using.

Command-B : Boldface the selected text, or turn boldfacing on or off.

Command-I : Italicize the selected text, or turn italics on or off.

Command-K : Add a web link.

Command-U : Underline the selected text, or turn underlining on or off.

Command-T : Show or hide the Fonts window.

Command-D : Select the Desktop folder from within an Open dialog or Save dialog.

Control-Command-D : Show or hide the definition of the selected word.

Shift-Command-Colon (:) : Display the Spelling and Grammar window.

Command-Semicolon (;) : Find misspelled words in the document.

Option-Delete : Delete the word to the left of the insertion point.

Control-H : Delete the character to the left of the insertion point. Or use Delete.

Control-D : Delete the character to the right of the insertion point. Or use Fn-Delete.

Fn-Delete : Forward delete on keyboards that don't have a Forward Delete key. Or use Control-D.

Control-K : Delete the text between the insertion point and the end of the line or paragraph.

Fn–Up Arrow : Page Up: Scroll up one page.

Fn–Down Arrow : Page Down: Scroll down one page.

Fn–Left Arrow: Home: Scroll to the beginning of a document.

Fn–Right Arrow : End: Scroll to the end of a document.

Command–Up Arrow : Move the insertion point to the beginning of the document.

Command–Down Arrow : Move the insertion point to the end of the document.

Command–Left Arrow : Move the insertion point to the beginning of the current line.

Command–Right Arrow : Move the insertion point to the end of the current line.

Option–Left Arrow : Move the insertion point to the beginning of the previous word.

Option–Right Arrow : Move the insertion point to the end of the next word.

Shift–Command–Up Arrow : Select the text between the insertion point and the beginning of the document.

Shift–Command–Down Arrow : Select the text between the insertion point and the end of the document.

Shift–Command–Left Arrow : Select the text between the insertion point and the beginning of the current line.

Shift–Command–Right Arrow : Select the text between the insertion point and the end of the current line.

Shift–Up Arrow : Extend text selection to the nearest character at the same horizontal location on the line above.

Shift–Down Arrow : Extend text selection to the nearest character at the same horizontal location on the line below.

Shift–Left Arrow : Extend text selection one character to the left.

Shift–Right Arrow : Extend text selection one character to the right.

Option–Shift–Up Arrow : Extend text selection to the beginning of the current paragraph, then to the beginning of the following paragraph if pressed again.

Option–Shift–Down Arrow : Extend text selection to the end of the current paragraph, then to the end of the following paragraph if pressed again.

Option–Shift–Left Arrow : Extend text selection to the beginning of the current word, then to the beginning of the following word if pressed again.

Option–Shift–Right Arrow : Extend text selection to the end of the current word, then to the end of the following word if pressed again.

Control-A : Move to the beginning of the line or paragraph.

Control-E : Move to the end of a line or paragraph.

Control-F : Move one character forward.

Control-B : Move one character backward.

Control-L : Center the cursor or selection in the visible area.

Control-P : Move up one line.

Control-N : Move down one line.

Control-O : Insert a new line after the insertion point.

Control-T : Swap the character behind the insertion point with the character in front of the insertion point.

Command–Left Curly Bracket ({) : Left align.

Command–Right Curly Bracket (}) : Right align.

Shift–Command–Vertical bar (|) : Center align.

Option-Command-F : Go to the search field.

Option-Command-T : Show or hide a toolbar in the app.

Option-Command-C : Copy Style: Copy the formatting settings of the selected item to the Clipboard.

Option-Command-V : Paste Style: Apply the copied style to the selected item.

Option-Shift-Command-V : Paste and Match Style: Apply the style of the surrounding content to the item pasted within that content.

Option-Command-I : Show or hide the inspector window.

Shift-Command-P : Page setup: Display a window for selecting document settings.

Shift-Command-S : Display the Save As dialog, or duplicate the current document.

Shift–Command–Minus sign (-) : Decrease the size of the selected item.

Shift–Command–Plus sign (+) : Increase the size of the selected item. Command–Equal sign (=) performs the same function.

Shift–Command–Question mark (?) : Open the Help menu.

To use these vision shortcuts, first choose Apple menu  > System Settings (or System Preferences), then click Keyboard. Click Keyboard Shortcuts, select Accessibility on the left, then select “Invert colors” and "Contrast" on the right.

Control-Option-Command-8 : Invert colors.

Control-Option-Command-Comma (,) and Control-Option-Command-Period (.) : Reduce contrast and increase contrast.

Use these shortcuts to change keyboard focus. To use some of these shortcuts, first choose Apple menu  > System Settings (or System Preferences), then click Keyboard. Click Keyboard Shortcuts, select Keyboard on the left, then select the shortcut's setting on the right.

Control-F2 or Fn-Control-F2: Move focus to the menu bar. You can then use the arrow keys to navigate the menu, press Return to open a selected menu or choose a selected menu item, or type the menu item's name to jump to that item in the selected menu.

Control-F3 or Fn-Control-F3 : Move focus to the Dock.

Control-F4 or Fn-Control-F4 : Move focus to the active window or next window.

Control-F5 or Fn-Control-F5 : Move focus to the window toolbar.

Control-F6 or Fn-Control-F6: Move focus to the floating window.

Control-Shift-F6 : Move focus to the previous panel.

Control-F7 or Fn-Control-F7 : Change the way Tab moves focus—between navigation of all controls on the screen, or only text boxes and lists.

Control-F8 or Fn-Control-F8 : Move focus to the status menu in the menu bar

Command–Grave accent (`) : Activate the next open window in the front app.

Shift–Command–Grave accent (`) : Activate the previous open window in the front app

Option–Command–Grave accent (`) : Move the focus to the window drawer.

Tab and Shift-Tab : Move to next control, move to previous control.

Control-Tab : Move to the next control when a text field is selected.

Control-Shift-Tab : Move to the previous grouping of controls.

Arrow keys : Move to the adjacent item in a list, tab group, or menu, or move sliders and adjusters (Up Arrow to increase values, Down Arrow to decrease values)

Control–Arrow keys : Move to a control adjacent to the text field.

Other accessibility shortcuts:

Option-Command-F5 or triple-press Touch ID : Show the Accessibility Shortcuts panel .

VoiceOver commands

Zoom in or out

Use Mouse Keys to control the pointer with your keyboard

If you're using VoiceOver, you might need to make VoiceOver ignore the next key press before you can use some of the shortcuts in this article.

Safari shortcuts

Spotlight shortcuts

Mail shortcuts

Photos shortcuts

Disk Utility shortcuts

Preview shortcuts

Apple Music shortcuts

Startup shortcuts

For more shortcuts, check the shortcut abbreviations shown in the menus of your apps. Every app can have its own shortcuts, and shortcuts that work in one app might not work in another.

Use emoji and symbols

Create your own shortcuts and resolve conflicts between shortcuts

Change the behavior of the function keys or modifier keys

Use a spoken command for a keyboard shortcut

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• Python Basics
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Python Operators

Precedence and associativity of operators in python.

• Python Arithmetic Operators
• Difference between / vs. // operator in Python
• Python - Star or Asterisk operator ( * )
• What does the Double Star operator mean in Python?
• Division Operators in Python
• Modulo operator (%) in Python
• Python Logical Operators
• Python OR Operator
• Difference between 'and' and '&' in Python
• not Operator in Python | Boolean Logic

Ternary Operator in Python

• Python Bitwise Operators

Python Assignment Operators

Assignment operators in python.

• Walrus Operator in Python 3.8
• Increment += and Decrement -= Assignment Operators in Python
• Merging and Updating Dictionary Operators in Python 3.9
• New '=' Operator in Python3.8 f-string

Python Relational Operators

• Comparison Operators in Python
• Python NOT EQUAL operator
• Difference between == and is operator in Python
• Chaining comparison operators in Python
• Python Membership and Identity Operators
• Difference between != and is not operator in Python

In Python programming, Operators in general are used to perform operations on values and variables. These are standard symbols used for logical and arithmetic operations. In this article, we will look into different types of Python operators. 

• OPERATORS: These are the special symbols. Eg- + , * , /, etc.
• OPERAND: It is the value on which the operator is applied.

Types of Operators in Python

• Arithmetic Operators
• Comparison Operators
• Logical Operators
• Bitwise Operators
• Assignment Operators
• Identity Operators and Membership Operators

Arithmetic Operators in Python

Python Arithmetic operators are used to perform basic mathematical operations like addition, subtraction, multiplication , and division .

In Python 3.x the result of division is a floating-point while in Python 2.x division of 2 integers was an integer. To obtain an integer result in Python 3.x floored (// integer) is used.

Example of Arithmetic Operators in Python

Division operators.

In Python programming language Division Operators allow you to divide two numbers and return a quotient, i.e., the first number or number at the left is divided by the second number or number at the right and returns the quotient. 

There are two types of division operators: 

Float division

• Floor division

The quotient returned by this operator is always a float number, no matter if two numbers are integers. For example:

Example: The code performs division operations and prints the results. It demonstrates that both integer and floating-point divisions return accurate results. For example, ’10/2′ results in ‘5.0’ , and ‘-10/2’ results in ‘-5.0’ .

Integer division( Floor division)

The quotient returned by this operator is dependent on the argument being passed. If any of the numbers is float, it returns output in float. It is also known as Floor division because, if any number is negative, then the output will be floored. For example:

Example: The code demonstrates integer (floor) division operations using the // in Python operators . It provides results as follows: ’10//3′ equals ‘3’ , ‘-5//2’ equals ‘-3’ , ‘ 5.0//2′ equals ‘2.0’ , and ‘-5.0//2’ equals ‘-3.0’ . Integer division returns the largest integer less than or equal to the division result.

Precedence of Arithmetic Operators in Python

The precedence of Arithmetic Operators in Python is as follows:

• P – Parentheses
• E – Exponentiation
• M – Multiplication (Multiplication and division have the same precedence)
• D – Division
• A – Addition (Addition and subtraction have the same precedence)
• S – Subtraction

The modulus of Python operators helps us extract the last digit/s of a number. For example:

• x % 10 -> yields the last digit
• x % 100 -> yield last two digits

Arithmetic Operators With Addition, Subtraction, Multiplication, Modulo and Power

Here is an example showing how different Arithmetic Operators in Python work:

Example: The code performs basic arithmetic operations with the values of ‘a’ and ‘b’ . It adds (‘+’) , subtracts (‘-‘) , multiplies (‘*’) , computes the remainder (‘%’) , and raises a to the power of ‘b (**)’ . The results of these operations are printed.

Note: Refer to Differences between / and // for some interesting facts about these two Python operators.

Comparison of Python Operators

In Python Comparison of Relational operators compares the values. It either returns True or False according to the condition.

= is an assignment operator and == comparison operator.

Precedence of Comparison Operators in Python

In Python, the comparison operators have lower precedence than the arithmetic operators. All the operators within comparison operators have the same precedence order.

Example of Comparison Operators in Python

Let’s see an example of Comparison Operators in Python.

Example: The code compares the values of ‘a’ and ‘b’ using various comparison Python operators and prints the results. It checks if ‘a’ is greater than, less than, equal to, not equal to, greater than, or equal to, and less than or equal to ‘b’ .

Logical Operators in Python

Python Logical operators perform Logical AND , Logical OR , and Logical NOT operations. It is used to combine conditional statements.

Precedence of Logical Operators in Python

The precedence of Logical Operators in Python is as follows:

• Logical not
• logical and

Example of Logical Operators in Python

The following code shows how to implement Logical Operators in Python:

Example: The code performs logical operations with Boolean values. It checks if both ‘a’ and ‘b’ are true ( ‘and’ ), if at least one of them is true ( ‘or’ ), and negates the value of ‘a’ using ‘not’ . The results are printed accordingly.

Bitwise Operators in Python

Python Bitwise operators act on bits and perform bit-by-bit operations. These are used to operate on binary numbers.

Precedence of Bitwise Operators in Python

The precedence of Bitwise Operators in Python is as follows:

• Bitwise NOT
• Bitwise Shift
• Bitwise AND
• Bitwise XOR

Here is an example showing how Bitwise Operators in Python work:

Example: The code demonstrates various bitwise operations with the values of ‘a’ and ‘b’ . It performs bitwise AND (&) , OR (|) , NOT (~) , XOR (^) , right shift (>>) , and left shift (<<) operations and prints the results. These operations manipulate the binary representations of the numbers.

Python Assignment operators are used to assign values to the variables.

Let’s see an example of Assignment Operators in Python.

Example: The code starts with ‘a’ and ‘b’ both having the value 10. It then performs a series of operations: addition, subtraction, multiplication, and a left shift operation on ‘b’ . The results of each operation are printed, showing the impact of these operations on the value of ‘b’ .

Identity Operators in Python

In Python, is and is not are the identity operators both are used to check if two values are located on the same part of the memory. Two variables that are equal do not imply that they are identical. 

Example Identity Operators in Python

Let’s see an example of Identity Operators in Python.

Example: The code uses identity operators to compare variables in Python. It checks if ‘a’ is not the same object as ‘b’ (which is true because they have different values) and if ‘a’ is the same object as ‘c’ (which is true because ‘c’ was assigned the value of ‘a’ ).

Membership Operators in Python

In Python, in and not in are the membership operators that are used to test whether a value or variable is in a sequence.

Examples of Membership Operators in Python

The following code shows how to implement Membership Operators in Python:

Example: The code checks for the presence of values ‘x’ and ‘y’ in the list. It prints whether or not each value is present in the list. ‘x’ is not in the list, and ‘y’ is present, as indicated by the printed messages. The code uses the ‘in’ and ‘not in’ Python operators to perform these checks.

in Python, Ternary operators also known as conditional expressions are operators that evaluate something based on a condition being true or false. It was added to Python in version 2.5. 

It simply allows testing a condition in a single line replacing the multiline if-else making the code compact.

Syntax :   [on_true] if [expression] else [on_false] 

Examples of Ternary Operator in Python

The code assigns values to variables ‘a’ and ‘b’ (10 and 20, respectively). It then uses a conditional assignment to determine the smaller of the two values and assigns it to the variable ‘min’ . Finally, it prints the value of ‘min’ , which is 10 in this case.

In Python, Operator precedence and associativity determine the priorities of the operator.

Operator Precedence in Python

This is used in an expression with more than one operator with different precedence to determine which operation to perform first.

Let’s see an example of how Operator Precedence in Python works:

Example: The code first calculates and prints the value of the expression 10 + 20 * 30 , which is 610. Then, it checks a condition based on the values of the ‘name’ and ‘age’ variables. Since the name is “ Alex” and the condition is satisfied using the or operator, it prints “Hello! Welcome.”

Operator Associativity in Python

If an expression contains two or more operators with the same precedence then Operator Associativity is used to determine. It can either be Left to Right or from Right to Left.

The following code shows how Operator Associativity in Python works:

Example: The code showcases various mathematical operations. It calculates and prints the results of division and multiplication, addition and subtraction, subtraction within parentheses, and exponentiation. The code illustrates different mathematical calculations and their outcomes.

To try your knowledge of Python Operators, you can take out the quiz on Operators in Python . 

Python Operator Exercise Questions

Below are two Exercise Questions on Python Operators. We have covered arithmetic operators and comparison operators in these exercise questions. For more exercises on Python Operators visit the page mentioned below.

Q1. Code to implement basic arithmetic operations on integers

Q2. Code to implement Comparison operations on integers

Explore more Exercises: Practice Exercise on Operators in Python

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Alito and the upside down flag: What the symbol means to 'stop the steal' crowd

An upside-down american flag is a symbol connected with false claims that the 2020 election was stolen from former president donald trump..

WASHINGTON − An upside-down American flag – a symbol connected with false claims that the 2020 election was stolen from former President Donald Trump − flew at the home of Supreme Court Justice Samuel Alito after the election, the New York Times reported Thursday.

The news came as the high court is deciding two cases related to the attempts by Trump and his supporters to overturn the results of the election, decisions that will affect the criminal election interference charge s pending against Trump. Supreme Court justices are supposed to avoid politics .

In a statement to The New York Times, Alito said he “had no involvement whatsoever in the flying of the flag.”

“It was briefly placed by Mrs. Alito in response to a neighbor’s use of objectionable and personally insulting language on yard signs,” he told the Times, referring to his wife Martha-Ann Alito.

Justice Alito says he couldn't tell his wife Martha-Ann Alito what to do

Alito told Fox News he didn’t have the right or ability to tell his wife what to do in the neighborhood dispute that began after the Jan. 6, 2021, attack on the Capitol.

Alito also said the neighbors’ sign she was reacting to by flying the upside-down flag blamed her for what happened on Jan. 6.

Inverted flags, a sign of distress, have been used by Trump supporters, particularly those protesting the 2020 election.

Kathleen Clark, a legal ethics expert at Washington University in St. Louis, who emphasized that she’s not an authority on the significance of an upside-down flag, said justices are not supposed to publicly display support or opposition to partisan political candidates.

“If it means `Stop the Steal,’ then it seems like he didn’t mind that ideological message going out to the world,” she said of the flag. “That’s political activity, arguably.”

More: Trump at Supreme Court: Ham sandwiches and solar eclipses - Justice Alito has questions

Calls for recusal

There have already been calls for Justice Clarence Thomas to recuse himself from those decisions because of his wife’s political advocacy.

Virginia  “Ginni” Thomas has argued repeatedly  the 2020 election was stolen and attended Trump’s “Stop the Steal” rally on Jan. 6, 2021.

Related: Amid blowback over Clarence Thomas travel, Supreme Court says it will adopt first-ever code of conduct

Stephen Gillers, a judicial ethics expert at New York University’s law school, told USA TODAY he doubts Alito knew the flag was flying upside down or, if he did know, wasn’t aware of the “Stop the Steal” connection.

“I don't believe Alito would have allowed this to happen if he did know,” Gillers said. “While Alito's explanation for how it did happen is hard to believe, it is more credible than the view that he knowingly chose to fly the flag upside down knowing its meaning to the "Stop the Steal" crowd.”

Alicia Bannon, director of the judiciary program at the Brennan Center for Justice, a liberal group, said a reasonable person could question Alito’s impartiality in the pending cases related to Jan. 6, 2021, and the charges Trump faces.

More: Justices Thomas, Alito complain about 'nastiness' and 'imperiled' freedom of religion

Alito, she tweeted, should recuse himself from those cases.

But both Bannon and Clark noted that the code of conduct the court adopted last year in response to ethics controversies does not include an enforcement mechanism.

“It's an acknowledgment that he needs to do something,” Clark said, “but it failed to do the most important thing which is provide a mechanism for accountability.”

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Origin claims on food labels

On this page, multiple country of origin statements, claims regarding the origin of ingredients or added value of a food, "local" claims, "product of canada" claims, "made in canada" claims with a qualifying statement, other domestic content claims, commodity specific information, official symbols of the government of canada, terms not subject to the guidelines, frequently asked questions, about shopping for canadian food.

In some cases, a company may choose to voluntarily declare the country of origin of the food product on the label, in order to further assist consumers in their purchasing decisions. A company may also choose to apply an origin claim regarding their food product or an ingredient contained within their food product. Guidance on the use of these types of claims can be found below.

The use of a voluntary multi-country of origin statement (for example, "Product of France and United States") is not acceptable. In this context, a product can only have one country of origin, which, at a minimum, is the country of last substantial transformation. All claims must be truthful and not misleading; declaring multiple countries of origin on the label may result in false information.

A blended claim, such as "A blend of [Naming the country] (naming the product) and [Naming the country] (naming the product)", may be considered (for example, "A blend of Brazilian and American soybean oil").

Guidance on the use of a voluntary multi-country of origin statement that includes or makes reference to Canada can be found below in the Guidelines for "Product of Canada" and "Made in Canada" claims .

A claim regarding the origin of ingredients within a food may be made, provided the claim is truthful and not misleading (for example, "Contains Italian olive oil"). In addition to this claim, a company may choose to highlight the amount of an ingredient in the food (for example, "10% Italian olive oil"). Further guidance on stressing or highlighting particular ingredients can be found in the Highlighted ingredients claims section.

Guidance on the use of claims regarding the Canadian origin of ingredients within a food can be found below in the Guidelines for "Product of Canada" and "Made in Canada" claims .

A claim regarding processing or added value that took place in a particular geographical origin may also be made on a food, provided the claim is truthful and not misleading (for example, "Packaged in Ireland").

A policy has been adopted which recognizes "local" food as:

• food produced in the province or territory in which it is sold, or
• food sold across provincial borders within 50 km of the originating province or territory

It is important to note that claims such as "local" are voluntary and industry is encouraged to add qualifiers, such as the name of a city, to provide consumers with additional information.

Guidelines for "Product of Canada" and "Made in Canada" claims

The guidelines for "Product of Canada" and "Made in Canada" claims promote compliance with subsection 5(1) of the Food and Drugs Act and subsection 6(1) of the Safe Food for Canadians Act , which prohibit false and misleading claims.

The use of "Product of Canada" and "Made in Canada" claims is voluntary. However, once a company chooses to make one of these claims, the product to which it is applied should meet these guidelines.

The guidelines for "Product of Canada" and "Made in Canada" claims apply to foods sold at all levels of trade, including bulk sale or wholesale foods for further processing. They also apply to claims made in advertising and by restaurants.

These guidelines do not apply to:

• these products must continue to meet the requirements of the importing country. This could result in different labels for domestic and exported products
• these products may be assessed under the Competition Bureau's Guide to "Made in Canada" claims
• content claims regarding regional or provincial content, such as provinces, cities, towns
• terms or references that have regulated requirements and are not subject to the guidelines (for example, grade names, references to Canada Organic or mandatory country of origin labelling)

All ingredients and their components that contribute to the food, regardless of their generation when they were added, must be considered when assessing "Product of Canada" and "Made in Canada" claims.

A food product may use the claim "Product of Canada" when all or virtually all major ingredients, processing, and labour used to make the food product are Canadian. This means that all the significant ingredients in a food product are Canadian in origin and that non-Canadian material is negligible.

The following circumstances would not disqualify a food from making a "Product of Canada" claim:

• very low levels of ingredients that are not generally produced in Canada, including spices, food additives, vitamins, minerals, flavouring preparations, or grown in Canada such as oranges, cane sugar and coffee. Generally, the percentage referred to as very little or minor is considered to be less than a total of 2% of the product
• packaging materials that are sourced from outside Canada, as these guidelines apply to the Canadian content and production or manufacturing of the food product and not the packaging itself
• the use of imported agricultural inputs such as seed, fertilizers, animal feed, and medications

For example, a cookie that is manufactured in Canada from oatmeal, enriched flour, butter, honey and milk from Canada, and imported vanilla, may use the claim "Product of Canada" even if the vitamins in the flour and the vanilla are not from Canada.

The claim "Canadian" is considered to be the same as a "Product of Canada" claim and any product carrying this claim must meet the criteria for a "Product of Canada" claim described above.

Generally, products that are exported and re-imported into Canada would not be able to make a "Product of Canada" claim.

The only exception would be if the product:

• meets the "Product of Canada" criteria, and
• is ready for sale when it leaves Canada (fully packaged and labelled) and is subsequently returned to Canada without undergoing any processing, repackaging or re-labelling (for example, perhaps because of an ordering error)

This is because all content, processing and labour still occurred in Canada.

A "Made in Canada" claim with a qualifying statement can be used on a food product when the last substantial transformation of the product occurred in Canada, even if some ingredients are from other countries.

Substantial transformation

A substantial transformation occurs when a food product undergoes processing which changes its nature and becomes a new product bearing a new name commonly understood by the consumer.

For example, the processing of cheese, dough, sauce and other ingredients to create a pizza would be considered a substantial transformation.

Qualifying statement

If the "Made in Canada" claim is used, it must also include a qualifying statement to indicate that the food product is made in Canada from imported ingredients or a combination of imported and domestic ingredients. The qualifying statements that can be used include "Made in Canada from domestic and imported ingredients" or "Made in Canada from imported ingredients".

All variations of "Made in Canada" claims must include a qualifying statement.

For example, a claim such as "Proudly Made in Canada" would need a qualifying statement if the product contains imported ingredients as this claim includes the phrase "Made in Canada".

Made in Canada from imported ingredients

When a food is made with ingredients that are all sourced from outside of Canada, the label would state "Made in Canada from imported ingredients".

For example, a cookie manufactured in Canada from imported flour, oatmeal, shortening and sugar may be labelled or advertised with the claim "Made in Canada from imported ingredients".

Made in Canada from domestic and imported ingredients

When a food contains both domestic and imported ingredients, the label would state "Made in Canada from domestic and imported ingredients". This claim may be used on a product that contains a mixture of imported and domestic ingredients, regardless of the level of Canadian content in the product.

For example, a cookie manufactured in Canada using Canadian flour, oatmeal and shortening and imported sugar may be labelled or advertised with the claim "Made in Canada from domestic and imported ingredients".

To provide clarity and consistency for consumers, when a company chooses to use the "Made in Canada" claim, the qualifying statement should be presented in a standard format: "from domestic and imported ingredients". However, it would be considered acceptable if the order were reversed, if there were a higher proportion of imported ingredients than domestic ingredients.

The claim "Made in Canada from domestic and/or imported ingredients" is not permitted as it does not provide meaningful information to the consumer about the Canadian content.

The use of "Product of Canada" and the qualified "Made in Canada" claims are encouraged to ensure clarity for the consumer and to enhance their ability to identify Canadian made foods. However, other more specific statements or claims that describe the Canadian value added may be used without further qualification, provided they are truthful and not misleading for consumers.

Examples of these types of domestic claims include:

• "Roasted and blended in Canada" to describe coffee since the coffee beans are always imported
• "Distilled in Canada" to describe bottled water that was distilled in Canada
• "Canned in Canada" to describe green beans that were canned in Canada
• "Refined in Canada" to describe imported cane sugar which has been refined in Canada
• "Processed in Canada" to describe a food which has been entirely processed in Canada
• "Prepared in Canada" to describe a food which has been entirely prepared in Canada
• "Packaged in Canada" to describe a food which is imported in bulk and packaged in Canada

Guidance on other types of commonly used domestic content claims can be found below:

Claims identifying a Canadian food or Canadian ingredients

The claim "Canadian" is considered to be the same as a "Product of Canada" claim. As such, all or virtually all major ingredients, processing, and labour used to make the food product must be Canadian. For example, the claim "Canadian" on a container of frozen lasagna would mean that the food meets the "Product of Canada" criteria.

This also applies when the claim is used to describe an ingredient within the food. For example, if the claim "Canadian cheddar cheese" is used on a package of cheddar cheese sauce, all or virtually all major ingredients, processing, and labour used to make the cheddar cheese in the sauce must be Canadian.

When this type of claim is used to describe a single component ingredient within the food, all of the ingredient(s) and, if any, derivatives of that ingredient in the food must be Canadian. For example, if the claim "Contains Canadian blueberries" is used on a prepackaged blueberry pie, all of the blueberries, as well as any blueberry juice concentrate or derivative, must be Canadian.

"100% Canadian" claims on foods or ingredients

When the claim "100% Canadian" is used on a label, the food or ingredient to which the claim applies must be entirely Canadian rather than "all or virtually all" Canadian.

For example, if the claim "100% Canadian" was used on a pot pie, all of the ingredients, processing, and labour used to make that product must be Canadian.

This would be the same case for a food with a claim which refers to the origin of a particular ingredient, whether single or multi-component, as being "100% Canadian".

For example, if the claim "Made with 100% Canadian wheat" is used on a bag of dry pasta, all of the wheat, and its derivatives, used in that product must be Canadian.

Additional guidance on the use of the claim "100% Canadian milk" can be found in the Guidelines for the acceptable use of "100% Canadian milk" claims on dairy products.

Multiple country of origin claims that reference Canada

The use of a voluntary multiple country of origin statement that references Canada (for example, "Product of Canada and United States") would not be acceptable. Products that contain foreign ingredients, regardless of their source, are not eligible to bear a "Product of Canada" claim.

Declaring multiple countries of origin on the label could result in false information and, as such, could be considered false and misleading.

Although products that contain foreign ingredients are not eligible to bear a "Product of Canada" claim, they may be eligible to make a qualified "Made in Canada" claim, provided that the last substantial transformation of the product occurred in Canada.

A blended claim, such as "A blend of Canadian (naming the product) and [Naming the country] (naming the product)", may be considered acceptable (for example, "A blend of Canadian and American soybean oil").

Separate requirements may exist for commodities that require a country of origin statement. These are summarized in the Food-specific labelling requirements section of the Industry Labelling Tool .

Meat and poultry

"Product of Canada" claims can be applied to meat from Canadian animals that are slaughtered in Canada. Animals are considered Canadian if they are born or hatched, raised and slaughtered in Canada or, in the case of feeder cattle, if they have spent a period of at least 60 days in Canada prior to slaughter in Canada. The 60-day residency period is based on international animal health standards. Such animals are fed, raised and slaughtered in Canada according to Canadian requirements.

Meat from imported hatching eggs, including those hatched in transit, would meet the "Product of Canada" guidelines provided that the chick was raised, slaughtered and processed in Canada.

Fish and seafood

Wild fish and seafood products can be labelled "Product of Canada" when caught by vessels in Canadian waters (or adjacent waters as per Canadian regulatory fishing quotas) and the products from the fish and seafood are processed in a Canadian establishment using Canadian ingredients.

In the case of farmed fish and seafood, the farm must be located in Canada, and the processing must occur in a Canadian establishment with the use of Canadian ingredients.

Dairy and eggs

Eggs from imported hens and milk from imported cows would qualify for the "Product of Canada" claim provided that the hen laid its eggs in Canada, and the cow is milked in Canada.

Symbols such as the Coat of Arms of Canada, the "Canada" Wordmark, and the Government of Canada Signature are normally reserved for use by the Government of Canada, and their commercial use is prohibited in most instances, except to acknowledge financial support from the Government of Canada . These symbols are the responsibility of the Treasury Board of Canada Secretariat (TBS). For more information, please see the TBS website on the legal protection of the official symbols of the Government of Canada .

National flag

The National Flag of Canada is protected by the Trademarks Act (TA) against unauthorized use for commercial purposes. No person shall adopt in connection with a business, as a trade mark or otherwise, any mark consisting of or likely to be mistaken for the flag adopted and used at any time by Canada in respect of which the Registrar has given public notice of its adoption and use [9(1), TA].

Requests to use the National Flag of Canada must be forwarded to the Department of Canadian Heritage: [email protected] .

The Department of Canadian Heritage requires users of the stylized 11-point maple leaf (the maple leaf of the National Flag of Canada) to obtain their permission. Requests to use the stylized 11-point maple leaf must be made to the Department of Canadian Heritage: [email protected] .

The maple leaf, other than the stylized 11-point maple leaf, or other similar symbol may be used on food products without further permission.

The use of these vignettes on their own does not always imply that the product is wholly or partially Canadian (for example, maple leaves as part of a fall scene on a product's label).

However, depending on how a maple leaf is used, it could imply a "Product of Canada" claim . In such situations, the product must follow the criteria for a "Product of Canada" claim. In order to ensure that the use of the maple leaf or other similar symbol will not mislead the consumer, it is recommended that an accompanying domestic content statement be placed in close proximity to the vignette.

The following terms or references have regulated requirements and, as such, are not subject to the guidelines for "Product of Canada" claims:

• the guidelines will not affect the regulated Canada grade name requirements or the inspection legend for edible meat products, processed egg products and prepackaged fish
• the Canada organic logo is an indication of organic certification to the Safe Food for Canadians Regulations . On imported products that are qualified to use the Canada organic logo, a country of origin statement or the statement "Imported" is required to be in close proximity to the logo, to avoid misleading consumers
• the guidelines do not apply to mandatory country of origin statements. In addition, the use of a qualified "Made in Canada" claim or any alternate claim, such as "Packaged in Canada" does not trigger the need for the country of origin declaration unless otherwise specified in regulations. For more information, refer to Country of origin labelling

Additional information

Refer to Frequently asked questions on "Product of Canada" and "Made in Canada" claims .

For more information on food that has been grown or made in Canada, refer to Shopping for Canadian food .