# The Min() And Max() Functions Of Ndarray

## Overiew:

• The min() and max() functions of numpy.ndarray returns the minimum and maximum values of an ndarray object.

• The return value of min() and max() functions is based on the axis specified.

• If no axis is specified the value returned is based on all the elements of the array.

## Example-ndarray.min(), ndarray.max():

• The example provided calls min() and max() functions on ndarray objects four times each.
• Once with no axis specified
• Thrice with axis values specified - the axis values are 0, 1 and 2.

• Since the ndarray object is a 3-dimensional array object it has 3 indexes.

• The dimension of the ndarray object is given by the tuple (3,3,4).

• That is the ndarray object has three 2-dimensional arrays of shape (3,4).

 # Example Python program for finding the min value along the given axis of an ndarray   # Import numpy module import numpy as np   # Import standard library module random import random   # Create a 3-Dimensional ndarray object array_3d = np.array([[[1,1,1,1],                      [2,2,2,2],                      [3,3,3,3]],                                          [[4,4,4,4],                      [5,5,5,5],                      [6,6,6,6]],                                          [[7,7,7,7],                      [8,8,8,8],                      [9,9,9,9]]]                     )                     # Print the 3-Dimensional Array print("Input ndarray:") print(array_3d)   print("Shape of the ndarray:") print(array_3d.shape)   print("Number of dimensions/axis of the ndarray:") print(array_3d.ndim)                       # Print the minimum value of the whole array - without considering the axis parameter print("Minimum value in the whole array:%d"%(array_3d.min()))                      # Print the minimum value for axis = 0 print("Minimum value along the axis 0:") print(array_3d.min(axis=0))   # Print the minimum value for axis = 1 print("Minimum value along the axis 1:") print(array_3d.min(axis=1))   # Print the minimum value for axis = 2 print("Minimum value along the axis 2:") print(array_3d.min(axis=2))   # Print the maximum value of the whole array - without considering the axis parameter print("Maximum value in the whole array:%d"%(array_3d.max()))                       # Print the maximum value for axis = 0 print("Maximum value along the axis 0:") print(array_3d.max(axis=0))   # Print the maximum value for axis = 1 print("Maximum value along the axis 1:") print(array_3d.max(axis=1))   # Print the maximum value for axis = 2 print("Maximum value along the axis 2:") print(array_3d.max(axis=2))

## Output:

 Input ndarray: [[[1 1 1 1]   [2 2 2 2]   [3 3 3 3]]    [[4 4 4 4]   [5 5 5 5]   [6 6 6 6]]    [[7 7 7 7]   [8 8 8 8]   [9 9 9 9]]] Shape of the ndarray: (3, 3, 4) Number of dimensions/axis of the ndarray: 3 Minimum value in the whole array:1 Minimum value along the axis 0: [[1 1 1 1]  [2 2 2 2]  [3 3 3 3]] Minimum value along the axis 1: [[1 1 1 1]  [4 4 4 4]  [7 7 7 7]] Minimum value along the axis 2: [[1 2 3]  [4 5 6]  [7 8 9]] Maximum value in the whole array:9 Maximum value along the axis 0: [[7 7 7 7]  [8 8 8 8]  [9 9 9 9]] Maximum value along the axis 1: [[3 3 3 3]  [6 6 6 6]  [9 9 9 9]] Maximum value along the axis 2: [[1 2 3]  [4 5 6]  [7 8 9]]