Concatenating NumPy Arrays Vertically

Python Pandas Numpy: Exercise-24 with Solution

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


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


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: Concatenating NumPy Arrays Vertically.

Python Code Editor:

Previous: Reshaping a 1D NumPy array into a 2D array.
Next: Matrix Multiplication with NumPy.

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