Python if greater than less than

The following example shows how to use the less than or equal to operator to compare two numbers:

>>> 20 20 True >>> 10 20 True >>> 30 30 TrueCode language: Python (python)

And this example shows how to use the less than or equal to operator to compare the values of two variables:

>>> x = 10 >>> y = 20 >>> x True >>> y FalseCode language: Python (python)

Greater than operator (>)

The greater than operator ( > ) compares two values and returns True if the left value is greater than the right value. Otherwise, it returns False :

left_value > right_valueCode language: Python (python)

This example uses the greater than operator ( > ) to compare two numbers:

>>> 20 > 10 True >>> 20 > 20 False >>> 10 > 20 FalseCode language: Python (python)

And the following example uses the greater than operator ( > ) to compare two strings:

>>> 'apple' > 'orange' False >>> 'orange' > 'apple' TrueCode language: Python (python)

Greater Than or Equal To operator ( >= )

The greater than or equal to operator ( >= ) compares two values and returns True if the left value is greater than or equal to the right value. Otherwise, it returns False :

left_value >= right_valueCode language: Python (python)

The following example uses the greater than or equal to operator to compare two numbers:

>>> 20 >= 10 True >>> 20 >= 20 True >>> 10 >= 20 FalseCode language: Python (python)

And the following example uses the greater than or equal to operator to compare two strings:

>>> 'apple' >= 'apple' True >>> 'apple' >= 'orange' False >>> 'orange' >= 'apple' TrueCode language: Python (python)

Equal To operator (==)

The equal to operator ( == ) compares two values and returns True if the left value is equal to the right value. Otherwise, it returns False :

left_value == right_valueCode language: Python (python)

The following example uses the equal to operator ( == ) to compare two numbers:

>>> 20 == 10 False >>> 20 == 20 TrueCode language: Python (python)

And the following example uses the equal to operator ( == ) to compare two strings:

>>> 'apple' == 'apple' True >>> 'apple' == 'orange' FalseCode language: Python (python)

Not Equal To operator (!=)

The not equal to operator ( != ) compares two values and returns True if the left value isn’t equal to the right value. Otherwise, it returns False .

left_value != right_valueCode language: Python (python)

For example, the following uses the not equal to operator to compare two numbers:

>>> 20 != 20 False >>> 20 != 10 TrueCode language: Python (python)

And the following example uses the not equal to operator to compare two strings:

>>> 'apple' != 'apple' False >>> 'apple' != 'orange' TrueCode language: Python (python)

Summary

• A comparison operator compares two values and returns a boolean value, either True or False .
• Python has six comparison operators: less than ( < ), less than or equal to ( ), greater than or equal to ( >= ), equal to ( == ), and not equal to ( != ).

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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 Comparison Operators

Operators are symbols in programming languages that perform the operation on the operands and decide the operation type. For instance, the equal to ( == ) operator checks for equal values and returns True if they are equal, and False otherwise, whereas the not equal ( !=) operator does the exact opposite.

In Python, operators can be divided into several categories based on their functionality such as Arithmetic Operators to perform mathematical operations, Comparison Operators to compare two values, Logical Operators to combine multiple conditions and evaluate whether they are True or False, Bitwise Operators to perform operations on the individual bits of a binary number, etc.

In this tutorial, we will learn about all types of Comparison Operators and demonstrate them with examples to understand their working.

Comparison Operators

Python comparison operators, also known as relational operators, are used in comparing two values and applying conditions respectively.

Here there can be two possible outputs, either boolean True or False .

There are several types of comparison operators, each performing a unique operation, let’s look at them one by one.

Types of Comparison Operators in Python

There are 6 types of comparison operators in Python:

1. Less Than ( < )
2. Greater Than ( > )
3. Equal To ( == )
4. Not Equal ( != )
5. Less Than or Equal To (
6. Greater Than or Equal To ( >= )

a = 10 if (a > 10): print("True") else: print("False")

a = 10 b = 20 if (a == b): print("True") else: print("False")

b is either less or equal to a

a = 5 b = 15 if(b >= a): print("b is either greater or equal to a")

b is either greater or equal to a

a = 10 b = 5 c = 0 if a == b: print("a is equal to b") else: print("a is not equal to b") if a != b: print("a is not equal to b") else: print("a is equal to b") if a < b: print("a is less than b") else: print("a is not less than b") if a >b: print("a is greater than b") else: print("a is not greater than b") a = 6; b = 15; if a = a: print("b is either greater than or equal to a") else: print("b is neither greater than nor equal to a")

a is not equal to b a is not equal to b a is not equal to b a is not less than b a is greater than b a is either less than or equal to b b is either greater than or equal to b