How to write a NumPy array with numeric data to a JSON file?

NumPy: I/O Operations Exercise-14 with Solution

Write a NumPy array with numeric data to a JSON file.

Sample Solution:

Python Code:

import numpy as np
import json

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

# Convert the NumPy array to a Python list
data_list = data_array.tolist()

# Define the path to the JSON file
json_file_path = 'data.json'

# Write the Python list to a JSON file
with open(json_file_path, 'w') as json_file:
    json.dump(data_list, json_file)

# Print a message indicating the JSON file has been written
print(f"Data has been written to {json_file_path}")

Output:

Data has been written to data.json

Explanation:

• Import NumPy and JSON Libraries: Import the NumPy and JSON libraries to handle arrays and JSON data.
• Create NumPy Array: Define a NumPy array with numeric data.
• Convert Array to List: Use the tolist() method to convert the NumPy array to a Python list because JSON format supports lists but not NumPy arrays directly.
• Define JSON File Path: Specify the path where the JSON file will be saved.
• Write List to JSON File: Open the JSON file in write mode using open(), then use json.dump() to write the Python list to the JSON file.
• Finally output a message indicating that the data has been successfully written to the JSON file.

Python-Numpy Code Editor:

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