NumPy: Save two given arrays into a single file in compressed format and load it

NumPy: Basic Exercise-36 with Solution

Write a NumPy program to save two given arrays into a single file in compressed format (.npz format) and load it.

Sample Solution :

Python Code :

# Importing the NumPy library with an alias 'np'
import numpy as np

# Importing the 'os' module for operating system-dependent functionality
import os

# Creating a NumPy array 'x' containing integers from 0 to 9 using np.arange()
x = np.arange(10)

# Creating a NumPy array 'y' containing integers from 11 to 19 using np.arange()
y = np.arange(11, 20)

# Printing a message indicating the original arrays 'x' and 'y'
print("Original arrays:")
print(x)
print(y)

# Saving the arrays 'x' and 'y' into a '.npz' file named 'temp_arra.npz' using np.savez()
np.savez('temp_arra.npz', x=x, y=y)

# Printing a message indicating loading arrays from the 'temp_arra.npz' file
print("Load arrays from the 'temp_arra.npz' file:")

# Loading data from 'temp_arra.npz' into variables 'x2' and 'y2' using np.load()
with np.load('temp_arra.npz') as data:
    x2 = data['x']
    y2 = data['y']
    
    # Printing the loaded arrays 'x2' and 'y2'
    print(x2)
    print(y2) 

Sample Output:

Original arrays:
[0 1 2 3 4 5 6 7 8 9]
[11 12 13 14 15 16 17 18 19]
Load arrays from the 'temp_arra.npz' file:
[0 1 2 3 4 5 6 7 8 9]
[11 12 13 14 15 16 17 18 19]                       

Explanation:

In the above exercise -

np.arange(10) creates a 1D array and stores in the variable 'x' with elements ranging from 0 to 9.

y = np.arange(11, 20): creates a 1D array and stores in 'y' with elements ranging from 11 to 19.

np.savez('temp_arra.npz', x=x, y=y): This line saves the NumPy arrays 'x' and 'y' to a compressed binary file named 'temp_arra.npz' using NumPy's native file format. The arrays are given the names 'x' and 'y' in the file.

with np.load('temp_arra.npz') as data:: This line opens the file 'temp_arra.npz' in read mode and loads its contents into a dictionary-like object called 'data'.

x2 = data['x']: This line extracts the 'x' array from the 'data' object and assigns it to the variable 'x2'.

y2 = data['y']: This line extracts the 'y' array from the 'data' object and assigns it to the variable 'y2'.

Finally print(x2) and print(y2) prints the loaded 'x2' array and 'y2' array.

Python-Numpy Code Editor:

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