Python using and in if statement

Python If . Else

Python supports the usual logical conditions from mathematics:

• Equals: a == b
• Not Equals: a != b
• Less than: a < b
• Less than or equal to: a
• Greater than: a > b
• Greater than or equal to: a >= b

These conditions can be used in several ways, most commonly in «if statements» and loops.

An «if statement» is written by using the if keyword.

Example

In this example we use two variables, a and b , which are used as part of the if statement to test whether b is greater than a . As a is 33 , and b is 200 , we know that 200 is greater than 33, and so we print to screen that «b is greater than a».

Indentation

Python relies on indentation (whitespace at the beginning of a line) to define scope in the code. Other programming languages often use curly-brackets for this purpose.

Example

If statement, without indentation (will raise an error):

Elif

The elif keyword is Python’s way of saying «if the previous conditions were not true, then try this condition».

Example

In this example a is equal to b , so the first condition is not true, but the elif condition is true, so we print to screen that «a and b are equal».

Else

The else keyword catches anything which isn’t caught by the preceding conditions.

Example

a = 200
b = 33
if b > a:
print(«b is greater than a»)
elif a == b:
print(«a and b are equal»)
else:
print(«a is greater than b»)

In this example a is greater than b , so the first condition is not true, also the elif condition is not true, so we go to the else condition and print to screen that «a is greater than b».

You can also have an else without the elif :

Example

Short Hand If

If you have only one statement to execute, you can put it on the same line as the if statement.

Example

Short Hand If . Else

If you have only one statement to execute, one for if, and one for else, you can put it all on the same line:

Example

One line if else statement:

This technique is known as Ternary Operators, or Conditional Expressions.

You can also have multiple else statements on the same line:

Example

One line if else statement, with 3 conditions:

And

The and keyword is a logical operator, and is used to combine conditional statements:

Example

Test if a is greater than b , AND if c is greater than a :

Or

The or keyword is a logical operator, and is used to combine conditional statements:

Example

Test if a is greater than b , OR if a is greater than c :

Not

The not keyword is a logical operator, and is used to reverse the result of the conditional statement:

Example

Test if a is NOT greater than b :

Nested If

You can have if statements inside if statements, this is called nested if statements.

Example

if x > 10:
print(«Above ten,»)
if x > 20:
print(«and also above 20!»)
else:
print(«but not above 20.»)

The pass Statement

if statements cannot be empty, but if you for some reason have an if statement with no content, put in the pass statement to avoid getting an error.

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Python using and in if statement

Last updated: Feb 18, 2023
Reading time · 4 min

# Check for multiple conditions in an if statement in Python

Use the boolean and operator to check for multiple conditions in an if statement.

The if block will only run if all of the conditions are met.

Copied! 
a = 1 b = 3 c = 7 # ✅ check for multiple conditions using AND if a == 1 and b == 3 and c == 7: # 👇️ this runs print('All conditions in the if statement are met') else: print('Not all conditions in the if statement are met') # -------------------------------------------- # ✅ check for multiple conditions using OR if a == 10 or b == 30 or c == 7: # 👇️ this runs print('One or more conditions in the if statement are met') else: print('None of the conditions in the if statement is met') 

The first example uses the boolean and operator to check for multiple conditions in an if statement.

You can use any of the comparison operators in the conditions.

Copied! 
a = 1 b = 3 c = 7 if a > 0 and b > 0 and c > 0: # 👇️ this runs print('All conditions in the if statement are met') else: print('Not all conditions in the if statement are met') 

The example checks if the variables a , b and c store values that are greater than 0 .

If any of the conditions evaluates to False , the interpreter short-circuits and doesn’t evaluate the next conditions.

# Using the all() function to check for multiple conditions in if

Alternatively, you can use the all() function.

Copied! 
a = 1 b = 3 c = 7 if all([a > 0, b > 0, c > 0]): # 👇️ this runs print('All conditions in the if statement are met') else: print('Not all conditions in the if statement are met') 

We passed a list containing multiple conditions to the all() function.

The all() built-in function takes an iterable as an argument and returns True if all elements in the iterable are truthy (or the iterable is empty).

If all of the conditions in the list evaluate to True , the if block runs, otherwise, the else block runs.

If one of the conditions isn’t met, the all() function will short-circuit and the else block will run.

# Check for multiple conditions using boolean OR

If you need to check if at least one condition is met, use the boolean OR operator.

The if block will run if at least one of the conditions is met.

Copied! 
a = 1 b = 3 c = 7 # ✅ check for multiple conditions using OR if a == 10 or b == 30 or c == 7: # 👇️ this runs print('One or more conditions in the if statement are met') else: print('None of the conditions in the if statement is met') 

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How to use AND Operator in Python IF Statement?

You can combine multiple conditions into a single expression in Python conditional statements like Python if, if-else and elif statements. This avoids writing multiple nested if statements unnecessarily.

In the following examples, we will see how we can use Python AND logical operator to form a compound logical expression.

Examples

1. If Statement with AND Operator

In the following example, we will learn how to use AND logical operator, in Python If statement, to join two boolean conditions to form a compound expression.

To demonstrate the advantage of and operator, we will first write a nested if, and then a simple if statement where in this simple if statement realizes the same functionality as that of nested if.

Python Program

a = 5 b = 2 #nested if if a==5: if b>0: print('a is 5 and',b,'is greater than zero.') #or you can combine the conditions as if a==5 and b>0: print('a is 5 and',b,'is greater than zero.')

Here, our use case is that, we have to print a message when a equals 5 and b is greater than 0. Without using and operator, we can only write a nested if statement, to program out functionality. When we used logical and operator, we could reduce the number of if statements to one.

a is 5 and b is greater than zero. a is 5 and b is greater than zero.

2. Python If-Else Statement with AND Operator

In the following example, we will use and operator to combine two basic conditional expressions in boolean expression of Python If-Else statement.

Python Program

a = 3 b = 2 if a==5 and b>0: print('a is 5 and',b,'is greater than zero.') else: print('a is not 5 or',b,'is not greater than zero.')

a is not 5 or 2 is not greater than zero.

3. Python elif Statement with AND Operator

In the following example, we will use and operator to combine two basic conditional expressions in boolean expression of Python elif statement.

Python Program

Summary

In this tutorial of Python Examples, we learned how to use Python and logical operator with Python conditional statement: if, if-else and elif with well detailed examples.

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