NumPy: Save as text a matrix which has in each row 2 float and 1 string at the end

NumPy: Array Object Exercise-164 with Solution

Save a matrix with mixed data types as text.

Write a NumPy program to save as text a matrix which has in each row 2 float and 1 string at the end.

Sample Solution:

Python Code:

# Importing the NumPy library
import numpy as np

# Creating a matrix (list of lists)
matrix = [
    [1, 0, 'aaa'],
    [0, 1, 'bbb'],
    [0, 1, 'ccc']
]

# Saving the matrix into a text file named 'test' using savetxt function
# Delimiter '  ' (two spaces) separates the values in the output file
# 'string' is the header written at the top of the file
# comments='' ensures no comments are included in the output file
# fmt='%s' specifies the format as string for all elements in the matrix
np.savetxt('test', matrix, delimiter='  ', header='string', comments='', fmt='%s') 

Sample Output:

string
1  0  aaa
0  1  bbb
0  1  ccc

Explanation:

matrix = [[1, 0, 'aaa'], [0, 1, 'bbb'], [0, 1, 'ccc']]: This line creates a 2D list (matrix) with the given elements.

np.savetxt('test', matrix, delimiter=' ', header='string', comments='', fmt='%s'): Call the np.savetxt() function with the following parameters:

• 'test': The name of the output file (without an extension).
• matrix: the 2D list to save to the file.
• delimiter: String or character separating columns.
• header: String that will be written at the beginning of the file.
• comments: String that will be prepended to the header and footer strings, to mark them as comments.
• fmt: A single format, a sequence of formats, or a multi-format string, (in this case, '%s', which indicates that the elements should be treated as strings).

The np.savetxt() function saves the matrix to a file named 'test' (with no file extension) using the said specified delimiter, header, comments, and format.

Python-Numpy Code Editor:

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