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Convert Height field to regular array in NumPy Structured array

NumPy: Structured Arrays Exercise-12 with Solution

Converting to Regular Arrays:

Write a NumPy program to convert the 'height' field of the structured array created with fields for 'name' (string), 'age' (integer), and 'height' (float) to a regular NumPy array.

Sample Solution:

Python Code:

import numpy as np

# Define the data type for the structured array
dtype = [('name', 'U10'), ('age', 'i4'), ('height', 'f4')]

# Create the structured array with sample data
structured_array = np.array([
    ('Lehi Piero', 25, 5.5),
    ('Albin Achan', 30, 5.8),
    ('Zerach Hava', 35, 6.1),
    ('Edmund Tereza', 40, 5.9),
    ('Laura Felinus', 28, 5.7)
], dtype=dtype)


print("Original Structured Array:")
print(structured_array)

# Convert the 'height' field to a regular NumPy array
height_array = structured_array['height']

# Print the regular NumPy array of 'height' field
print("\nRegular NumPy array of 'height' field:")
print(height_array)

Output:

Original Structured Array:
[('Lehi Piero', 25, 5.5) ('Albin Acha', 30, 5.8) ('Zerach Hav', 35, 6.1)
 ('Edmund Ter', 40, 5.9) ('Laura Feli', 28, 5.7)]

Regular NumPy array of 'height' field:
[5.5 5.8 6.1 5.9 5.7]

Explanation:

  • Import Libraries:
    • Imported numpy as "np" for array creation and manipulation.
  • Define Data Type:
    • Define the data type for the structured array using a list of tuples. Each tuple specifies a field name and its corresponding data type. The data types are:
      • 'U10' for a string of up to 10 characters.
      • 'i4' for a 4-byte integer.
      • 'f4' for a 4-byte float.
  • Create a Structured Array:
    • Created the structured array using np.array(), providing sample data for five individuals. Each individual is represented as a tuple with values for 'name', 'age', and 'height'.
  • Convert 'Height' Field to Regular Array:
    • Converted the 'height' field to a regular NumPy array by accessing structured_array['height'].
  • Print a Regular Array:
    • Print the regular NumPy array of the 'height' field to verify the conversion.

Python-Numpy Code Editor: