# All() And Any() Functions On Numpy.ndarray

## Overview:

• Given an n-dimensional matrix, its contents can be checked whether all of its elements evaluate to True or any of its elements evaluate to True.

• The all() method of numpy.ndarray can be used to check whether all of the elements of an ndarray object evaluate to True.

• The any() method of numpy.ndarray  can be used to find whether any of the elements of an ndarray object evaluate to True.

• These tests can be performed considering the n-dimensional array as a flat array or over a specific axis of the array.

• When the axis is not specified these operations are performed on the whole array and when the axis is specified these operations are performed on the given axis.

• While all() method performs a logical AND operation on the ndarray elements or the elements along the given axis of the ndarray, the any() method performs a logical OR operation.

## Example: numpy.ndarray.all()

 import numpy as np   # Create a 3 dimensional array Array_3d = np.arange(9).reshape(3,3)   print("2 dimensional input array:") print(Array_3d)   print("Return values from all():") print("-------------------------") print("When no axis is specified:") print(Array_3d.all()) print("When no axis is specified and keepdims = True:") print(Array_3d.all(keepdims=True)) print("When axis=0") print(Array_3d.all(axis=0)) print("When axis=0,  keepdims = True:") print(Array_3d.all(axis=0, keepdims=True))

## Output:

 2 dimensional input array: [[0 1 2]  [3 4 5]  [6 7 8]] Return values from all(): ------------------------- When no axis is specified: False When no axis is specified and keepdims = True: [[False]] When axis=0 [False  True  True] When axis=0,  keepdims = True: [[False  True  True]]

## Example: numpy.ndarray.any()

 import numpy as np   # Create a 3 dimensional array Array_3d = np.arange(9).reshape(3,3)   print("2 dimensional input array:") print(Array_3d)   print("Return values from any():") print("-------------------------") print("When no axis is specified:") print(Array_3d.any()) print("When no axis is specified and keepdims = True:") print(Array_3d.any(keepdims=True)) print("When axis=0") print(Array_3d.any(axis=0)) print("When axis=0,  keepdims = True:") print(Array_3d.any(axis=0, keepdims=True))

## Output:

 2 dimensional input array: [[0 1 2]  [3 4 5]  [6 7 8]] Return values from any(): ------------------------- When no axis is specified: True When no axis is specified and keepdims = True: [[ True]] When axis=0 [ True  True  True] When axis=0,  keepdims = True: [[ True  True  True]]