In this article, we will learn to compare two NumPy Arrays element-wise using Python.

**Table Of Contents**

There are the multiple ways to compare two NumPy Arrays element-wise. Let’s discuss them one by one.

## Compare two NumPy Arrays using == operator

When two numpy arrays are compared using == operator, it will return a boolean array. If any value in the boolean array is true, then the corresponding elements in the both the arrays are equal, otherwise not equal.

**Approach:**

- Import NumPy library.
- Create two numpy arrays of equal length.
- apply the
`==`

operator on both the arrays, i.e,`arr1 ==arr2`

. It will return a bool array. - Call the all() function on bool array. If it returns True, it means both arrays are equal, otherwise not.

**Source Code**

import numpy as np # creating two numpy arrays a = np.array([1, 2, 8, 7, 5]) b = np.array([1, 2, 3, 2, 5]) # comparing the arrays using == operator arr = a==b print(arr) if arr.all(): print('Both arrays are equal') else: print('Both Arrays are not equal')

**Output:**

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[ True True False False True] Both Arrays are not equal

The comparision can aslo be done with greater than (>) and less than (<) operators. The boolean array elements will contain true if the applied operator is true else false.

**Code using > and < operator**

import numpy as np # creating two numpy arrays a = np.array([1, 2, 8, 7, 5]) b = np.array([1, 2, 8, 7, 5]) # comparing the arrays using > operator print("comparing the arrays using > operator ", a > b) # comparing the arrays using < operator print("comparing the arrays using < operator ", a < b) if ( (~(a < b)).all() and (~(a > b)).all() ): print('Both arrays are equal') else: print('Both Arrays are not equal')

**Output:**

comparing the arrays using > operator [False False False False False] comparing the arrays using < operator [False False False False False] Both arrays are equal

## Compare two NumPy Arrays using for loop and zip()

The zip() method takes multiple iterables as arguments and yeilds n-length tuple. Where n is the number of iterables passed to it. Now using for loop and zip() we will iterate over both the arrays and compare them element-wise.

Approach:

- Import NumPy library.
- Create two numpy arrays of equal length.
- Iterate over array and compare elements
- Print the boolean array.

**Source Code**

import numpy as np # Creating two numpy arrays a = np.array([1, 2, 8, 7, 5]) b = np.array([1, 2, 3, 4, 5]) # Comparing the arrays using == comparision = [] for i,j in zip(a,b): if i==j: comparision.append(True) else: comparision.append(False) print(comparision) if all(comparision): print('Both arrays are equal') else: print('Both Arrays are not equal')

**Output:**

[True, True, False, False, True] Both Arrays are not equal

The comparision can aslo be done with greater than (>) and less than (<) operators. By replacing `==`

with `>`

or `<`

operator.

## Compare two NumPy Arrays using for loop

Iterate over the array and compare each element using `==, > or <`

operators. For accesing the elements of both the arrays use indexing.

**Approach:**

- Import NumPy library.
- Create two numpy arrays of equal length.
- Iterate over array using for loop and compare elements
- print the boolean array.

**Source Code**

import numpy as np # creating two numpy arrays a = np.array([1, 2, 8, 7, 5]) b = np.array([1, 2, 3, 4, 5]) # comparing the arrays using == comparision = [] for i in range(np.size(a)): if a[i]==b[i]: comparision.append(True) else: comparision.append(False) print(" comparision using ==", comparision) if all(comparision): print('Both arrays are equal') else: print('Both Arrays are not equal') # comparing the arrays using > comparision = [] for i in range(np.size(a)): if a[i] > b[i]: comparision.append(True) else: comparision.append(False) print(" comparision using >", comparision) if all(comparision): print('Both arrays are equal') else: print('Both Arrays are not equal') # comparing the arrays using < comparision = [] for i in range(np.size(a)): if a[i] < b[i]: comparision.append(True) else: comparision.append(False) print(" comparision using <", comparision) if all(comparision): print('Both arrays are equal') else: print('Both Arrays are not equal')

**Output:**

comparision using == [True, True, False, False, True] Both Arrays are not equal comparision using > [False, False, True, True, False] Both Arrays are not equal comparision using < [False, False, False, False, False] Both Arrays are not equal

## Compare two NumPy Arrays using List Comprehension

Using list comprehension, iterate over the array and compare each element using `==, > or <`

operator.

**Approach:**

- Import NumPy library.
- Create two numpy arrays of equal length.
- Use list comprehension to compare the elements.
- Print the boolean array.

**Source Code**

import numpy as np # creating two numpy arrays a = np.array([1, 2, 8, 7, 5]) b = np.array([1, 2, 3, 4, 5]) # comparing the arrays using == comparision = [i==j for i,j in zip(a,b)] if all(comparision): print('Both arrays are equal') else: print('Both Arrays are not equal') # comparing the arrays using > comparision = [i > j for i,j in zip(a,b)] if all(comparision): print('Both arrays are equal') else: print('Both Arrays are not equal') # comparing the arrays using < comparision = [i < j for i,j in zip(a,b)] if all(comparision): print('Both arrays are equal') else: print('Both Arrays are not equal')

**Output:**

Both Arrays are not equal Both Arrays are not equal Both Arrays are not equal

## Compare two NumPy Arrays using while loop

Iterate over the array using while loop and compare each element using `==, > or <`

operator. For accesing the elements of both the arrays use indexing.

**Approach:**

- Import NumPy library.
- Create two numpy arrays of equal length.
- Iterate over array using while loop and compare elements.
- print the boolean array.

**Source Code**

import numpy as np # creating two numpy arrays a = np.array([1, 2, 8, 7, 5]) b = np.array([1, 2, 3, 4, 5]) # comparing the arrays using == comparision = [] i = 0 while(i < np.size(a)): if a[i]==b[i]: comparision.append(True) else: comparision.append(False) i+=1 print(" comparision using ==", comparision) # comparing the arrays using > comparision = [] i = 0 while(i < np.size(a)): if a[i]==b[i]: comparision.append(True) else: comparision.append(False) i+=1 print(" comparision using >", comparision) # comparing the arrays using < comparision = [] i = 0 while(i < np.size(a)): if a[i]==b[i]: comparision.append(True) else: comparision.append(False) i+=1 print(" comparision using <", comparision)

**Output**

comparision using == [True, True, False, False, True] comparision using > [True, True, False, False, True] comparision using < [True, True, False, False, True]

## Summary

Great! you made it, We have discussed All possible methods to compare two NumPy Arrays element-wise using Python. Happy learning.