learn-python/contrib/numpy/saving_numpy_arrays_to_files.md

Saving NumPy Arrays to Files

• Saving arrays in NumPy is important due to its efficiency in storage and speed, maintaining data integrity and precision, and offering convenience and interoperability.
• NumPy provides several methods to save arrays efficiently, either in binary or text formats.
• The primary methods are save, savez, and savetxt.

1. numpy.save():

The np.save function saves a single NumPy array to a binary file with a .npy extension. This format is efficient and preserves the array's data type and shape.

Syntax :

numpy.save(file, arr, allow_pickle=True, fix_imports=True)

• file : Name of the file.
• arr : Array to be saved.
• allow_pickle : This is an Optional parameter, Allows saving object arrays using Python pickles.(By Default True)
• fix_imports : This is an Optional parameter, Fixes issues for Python 2 to Python 3 compatibility.(By Default True)

Example :

import numpy as np

arr = np.array([1,2,3,4,5])
np.save("example.npy",arr) #saves arr into example.npy file in binary format

Inorder to load the array from example.npy

arr1 = np.load("example.npy")
print(arr1)

Output :

[1,2,3,4,5]