Save and load NumPy array to CSV with custom delimiter
NumPy: I/O Operations Exercise-20 with Solution
Write a NumPy array to a CSV file with a custom delimiter and then read it back into a NumPy array using the same delimiter.
Sample Solution:
Python Code:
import numpy as np
# Create a NumPy array
array_to_save = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
# Define the file name to save the CSV file
csv_file_name = 'array_data.csv'
# Save the NumPy array to a CSV file with a custom delimiter
np.savetxt(csv_file_name, array_to_save, delimiter=';', fmt='%d')
# Load the data back from the CSV file using the same delimiter
loaded_array = np.loadtxt(csv_file_name, delimiter=';')
# Print the loaded array to verify it matches the original array
print('Loaded array:\n', loaded_array)
Output:
Loaded array: [[1. 2. 3.] [4. 5. 6.] [7. 8. 9.]]
Explanation:
- Import Libraries:
- Imported numpy as np for handling arrays and file operations.
- Create NumPy Array:
- Created a 3x3 NumPy array named array_to_save.
- Define File Name:
- Set the CSV file name to array_data.csv.
- Save Array to CSV with Custom Delimiter:
- Used np.savetxt to save array_to_save to the CSV file, specifying ; as the custom delimiter and formatting the numbers as integers ('%d').
- Load Data from CSV with Same Delimiter:
- Used np.loadtxt to read the data from the CSV file into loaded_array, using ; as the delimiter.
- Print Loaded Array:
- Printed the loaded array to verify it matches the original array.
Python-Numpy Code Editor:
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