How to save a NumPy array to a text file and read it back?

Last update on December 21 2024 07:40:09 (UTC/GMT +8 hours)

NumPy: I/O Operations Exercise-6 with Solution

Write a NumPy program that saves a NumPy array to a text file with space as the delimiter and then reads it back into a NumPy array.

Sample Solution:

Python Code:

import numpy as np

# Create a NumPy array
data_array = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])

# Define the path to the text file
text_file_path = 'data.txt'

# Save the NumPy array to a text file with space as the delimiter
np.savetxt(text_file_path, data_array, delimiter=' ')

# Read the text file back into a NumPy array
loaded_array = np.loadtxt(text_file_path, delimiter=' ')

# Print the original and loaded NumPy arrays
print("Original NumPy Array:")
print(data_array)

print("\nLoaded NumPy Array from Text File:")
print(loaded_array)

Output:

Original NumPy Array:
[[1 2 3]
 [4 5 6]
 [7 8 9]]

Loaded NumPy Array from Text File:
[[1. 2. 3.]
 [4. 5. 6.]
 [7. 8. 9.]]

Explanation:

Import NumPy Library: Import the NumPy library to handle arrays.
Create NumPy Array: Define a NumPy array with some example data.
Define Text File Path: Specify the path where the text file will be saved.
Save Array to Text File: Use np.savetxt() to save the NumPy array to a text file, specifying space as the delimiter.
Read Text File into NumPy Array: Use np.loadtxt() to read the contents of the text file back into a NumPy array, specifying space as the delimiter.
Print Original and Loaded Arrays: Output both the original NumPy array and the loaded array to verify that the data was saved and read correctly.

Python-Numpy Code Editor: