NumPy: Merge three given NumPy arrays of same shape

NumPy: Array Object Exercise-165 with Solution

Merge three arrays of the same shape.

Write a NumPy program to merge three given NumPy arrays of same shape.

Sample Solution:

Python Code:

# Importing the NumPy library
import numpy as np

# Creating three random arrays of shape (25, 25, 1)
arr1 = np.random.random(size=(25, 25, 1))
arr2 = np.random.random(size=(25, 25, 1))
arr3 = np.random.random(size=(25, 25, 1))

# Printing the original arrays
print("Original arrays:")
print(arr1)
print(arr2)
print(arr3)

# Concatenating the arrays along the last axis (-1) using np.concatenate
result = np.concatenate((arr1, arr2, arr3), axis=-1)

# Printing the concatenated array
print("\nAfter concatenate:")
print(result)

Sample Output:

Original arrays:
[[[2.42789481e-01]
  [4.92252795e-01]
  [9.33448807e-01]
  [7.25450297e-01]
  [9.74093474e-02]
  [5.68505405e-01]
  [9.65681560e-01]
  [7.94931731e-01]
  [7.52893987e-01]
  [5.43942380e-01]
  [9.38096939e-01]
  [8.38066653e-01]
  [7.83185689e-01]
  [4.22962615e-02]
  [2.96843761e-01]
  [9.50102088e-01]
  [6.36912393e-01]
  [3.75066692e-03]
  [6.03600756e-01]
  [4.22466907e-01]
  [3.23442622e-01]
  [7.23251484e-02]
  [1.49598420e-01]
  [5.45714254e-01]
  [9.59122727e-01]]
.........

After concatenate:
[[[0.24278948 0.41363799 0.00761597]
  [0.4922528  0.8033311  0.73833312]
  [0.93344881 0.55224706 0.72935665]
  ...
  [0.14959842 0.26294052 0.63326384]
  [0.54571425 0.82177763 0.7713901 ]
  [0.95912273 0.39791879 0.7461949 ]]

 [[0.58204652 0.28280547 0.32875312]
  [0.05928564 0.63875077 0.85676908]
  [0.02107624 0.37230817 0.32580032]
  ...

  [0.81238835 0.16140993 0.79200889]
  [0.01420085 0.77062809 0.56002668]
  [0.34129681 0.60455665 0.91487593]]

 [[0.61701713 0.53000888 0.91511595]
  [0.59898594 0.74249711 0.26521013]
  [0.17960885 0.93751794 0.65149374]
  ...
  [0.57535478 0.35775559 0.37634059]
  [0.85069491 0.80337115 0.21084745]
  [0.5365623  0.512

Explanation:

arr1 = np.random.random(size=(25, 25, 1))

arr2 = np.random.random(size=(25, 25, 1))

arr3 = np.random.random(size=(25, 25, 1))

The above three statements create three 3D NumPy arrays (arr1, arr2, arr3) with shape (25, 25, 1). The elements are random numbers between 0 and 1 generated by the np.random.random() function.

result = np.concatenate((arr1, arr2, arr3), axis=-1): This line concatenate the three arrays along the last axis (axis=-1) using the np.concatenate() function. Since the last axis has size 1, concatenating the three arrays along this axis will create a new array with shape (25, 25, 3).

Pictorial Presentation:

Python-Numpy Code Editor:

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