NumPy: Remove the first dimension from a given array of shape (1,3,4)

NumPy: Array Object Exercise-195 with Solution

Remove first dimension of a (1,3,4) array.

Write a NumPy program to remove the first dimension from a given array of shape (1,3,4).

Sample array:
[[[1, 2, 3, 4],
[0, 1, 3, 4],
[5, 0, 3, 2]]])

Sample Solution:

Python Code:

# Importing NumPy library
import numpy as np

# Creating a NumPy array with a shape of (1, 3, 4) containing nested lists
nums = np.array([[[1, 2, 3, 4],
                  [0, 1, 3, 4],
                  [5, 0, 3, 2]]])

# Printing the shape of the array
print('Shape of the said array:')
print(nums.shape)

# Removing the first dimension of the array's shape using slicing
# The result will have a shape of (3, 4)
result = nums[0]
print("\nAfter removing the first dimension of the shape of the said array:")
print(result.shape) 

Sample Output:

Shape of the said array:
(1, 3, 4)

After removing the first dimension of the shape of the said array:
(3, 4)

Explanation:

In the above exercise -

The NumPy code first creates a 3-dimensional array nums with shape (1, 3, 4).

print(nums.shape): The print() function prints the shape of the “nums” array.

new_array = np.squeeze(nums, axis=0): Here, the np.squeeze() function is used to remove the first dimension (axis=0) of the "nums" array. The result is assigned to the variable "new_array".

print(new_array.shape): Finally print() function prints the shape of the “new_array” which returns (3, 4).

Python-Numpy Code Editor:

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