How to read a CSV file into a NumPy array and print it?

Last update on March 26 2025 13:12:09 (UTC/GMT +8 hours)

15. CSV to Array Conversion

Write a NumPy program to read a CSV file into a NumPy array and print the array.

Sample Solution:

Python Code:

import numpy as np

# Read a CSV file into a NumPy array
# Ensure the 'array.csv' file exists in the working directory
array = np.loadtxt('array.csv', delimiter=',')

# Print the NumPy array
print(array)

Output:

[[1. 2. 3.]
 [4. 5. 6.]
 [7. 8. 9.]]

Explanation:

• Import NumPy Library: Import the NumPy library to work with arrays.
• Read CSV File into NumPy Array: Use np.loadtxt() to read the contents of a CSV file named 'array.csv' into a NumPy array, specifying the delimiter as a comma.
• Print NumPy Array: Output the resulting NumPy array to verify the data read from the CSV file.

For more Practice: Solve these Related Problems:

• Write a Numpy program to read a CSV file into a NumPy array and then reshape the array based on metadata provided in the file.
• Write a Numpy program to import a CSV file containing mixed data types into a NumPy array while applying type conversion rules.
• Write a Numpy program to read a CSV file into a NumPy array and handle missing values by replacing them with column means.
• Write a Numpy program to load a CSV file into a NumPy array and then perform vectorized filtering to extract rows matching a criterion.

Python-Numpy Code Editor:

Previous: How to save a NumPy array to a CSV File and verify contents?
Next: How to convert a 3D NumPy array to a list of lists of lists?