In this Python tutorial, you will learn how to use the “not equal” operator in Python.
Table Of Contents
Let’s dive into the tutorial.
“not equal” operator (!=) in Python
In Python, we will use != as the “not equal” operator. It is used to compare two expressions/operators and return True if they are not equal, otherwise, it will return False.
Syntax:
operand1 != operand2
where operand1 is the first operand and operand2 is the second operand.
Example:
Frequently Asked:
- Python – if…elif…else statement
- Logical “and” & “or” with if statement in Python
- Python: if-else in one line – ( A Ternary operator )
- Conditional Expressions in Python
In this example, we will apply the != operator on different operands.
# Check 34 is not equal to 56. print(34 != 56) # Check 34 is not equal to 34. print(34 != 34) # Check "thisPointer" is not equal to "python". print("thisPointer" != "python")
Output:
True False True
We can see that
- 34 is not equal to 56, hence the output is True
- 34 is equal to 34, hence the output is False
- thisPointer is not equal to python, hence the output is True
If the variable is the same, but the data type of variable is different, In that case,
- Integer type and string type are different. So != returns True
- Integer type and double type are the same. So != returns False
- string type and double type are different. So != returns True
Example:
In this example, we will demonstrate the above scenario.
# check if 34 is not equal to '34' print(34 != '34') # check if 34 is not equal to 34.0 print(34 != 34.0) # check if 34.0 is not equal to '34' print(34.0 != '34')
Output:
True False True
In the above code, we are
- Comparing integer type 34 with string type 34
- Comparing integer type 34 with double type 34
- Comparing double type 34 with string type 34
“not equal” Operator ( != ) in conditional statements
If we want to compare any expressions using the not equal operator in conditional statements like if,if-else, then we can use it.
Syntax:
if(operand/expression != operand/expression): statements ......... ......... elif(operand/expression != operand/expression): statements ......... ......... else: statements ......... .........
Example 1:
In this example, we will create two variables and compare the expressions with != operator.
# Create two variables a=43 b=77 # check if a+b is not equal to a*b # if true, assign a and b to 100 if(a+b != a*b): a=100 b=100 print(a,b) else: # otherwise display a and b print(a,b)
Output:
100 100
In the above code, we are evaluating the expressions a+b and ab. If they are not equal, and the if block is executed if value of (a + b) is not equal to (a * b)*, otherwise else block is executed by displaying actual values of a and b.
We can see that if block is executed. Hence the output is 100 100
Example 2:
In this example, we will create two variables and compare the expression and an operand with != operator.
# create two variables a=43 b=77 # check if a+b is not equal to 120 # if true, assign a and b to 100 if(a + b != 120): a=100 b=100 print(a,b) else: # otherwise display a and b print(a,b)
Output:
43 77
In the above code, we are evaluating the expression a+b and compared it with 120. If they are not equal the the if block is executed and values of a and b are updated to 100. Otherwise the else block is executed by displaying the actual values of a and b.
We can see that else block is executed. Hence the output is 43 77.
“not equal” operator (!=) in Loops in Python
It is possible to use != operator with conditional statements under looping structures like for loop, while loop.
Syntax:
for iterator in range(sequence): if(iterator != operand/expression): statements ......... ......... elif(iterator != operand/expression): statements ......... ......... else: statements ......... .........
Where, an iterator is used to iterate the sequence of elements inside for loop.
Example:
In this example, we are iterating elements from 20 to 30 inside for loop and if the iterator is not equal to 25, we are displaying the iterator.
# iterate elements from 20 to 30 for iterator in range(20,30): # If the iterator not equals to 25 # then display the iterator if(iterator != 25): print(iterator)
Output:
20 21 22 23 24 26 27 28 29
We can see that 25 is not displayed.
“not equal” operator (!=) with Data Structures in Python
We can also use the != operator with the Python data structures like list, tuple, dictionary, and set. Elements inside these data structures can be compared using this != operator.
We can use for loop to iterate elements inside these data structures and conditional statements inside for loop. The != operator is also used in conditional statements.
Example:
In this example, we created a list and tuple with 5 string elements each and iterate these elements inside for loop and compare each value with != operator.
# Create list list1=["welcome","to","thispointer","python","tutorial"] # Create tuple tuple1=("welcome","to","thispointer","python","tutorial") # for loop to iterate elements inside list1 for iterator in list1: # Check if iterator is not equal to python if(iterator!="python"): print(iterator, end=" ") print("") # for loop to iterate elements inside tuple1 for iterator in tuple1: # Check if iterator is not equal to "tutorial" if(iterator != "tutorial"): print(iterator, end=" ") print("")
Output:
welcome to thispointer tutorial welcome to thispointer python
Summary
By the end of this tutorial, you must have noticed that the != operator had a vast range of applications. It can be used everywhere. So based on the requirement, you can use this not equal operator in Python. Happy Learning