Concatenating NumPy Arrays Vertically

Last update on December 21 2024 07:43:21 (UTC/GMT +8 hours)

Concatenate two NumPy arrays vertically.

Sample Solution:

Python Code:

import numpy as np

# Create two NumPy arrays
array1 = np.array([[1, 2, 3],
                   [4, 5, 6]])

array2 = np.array([[7, 8, 9],
                   [10, 11, 12]])

# Concatenate arrays vertically
result_array = np.vstack((array1, array2))

# Display the result
print(result_array)

Output:

[[ 1  2  3]
 [ 4  5  6]
 [ 7  8  9]
 [10 11 12]]

Explanation:

Here's a breakdown of the above code:

• We created two NumPy arrays, "array1" and "array2", each with two rows and three columns.
• The np.vstack((array1, array2)) function concatenates the arrays vertically.
• The resulting result_array is a NumPy array with four rows and three columns.
• The result is printed, showing the vertically concatenated array.

We can also use np.concatenate() with axis=0 for vertical concatenation:

result_array = np.concatenate((array1, array2), axis=0)

Flowchart:

Python Code Editor:

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