Combine two Structured arrays in NumPy

NumPy: Structured Arrays Exercise-10 with Solution

Combining Structured Arrays:

Write a NumPy program that combines two structured arrays with the same dtype into one.

Sample Solution:

Python Code:

import numpy as np

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

# Create the first structured array with sample data
structured_array1 = np.array([
    ('Lehi', 25, 5.5),
    ('Albin', 30, 5.8)
], dtype=dtype)

# Create the second structured array with sample data
structured_array2 = np.array([
    ('Zerach', 35, 6.1),
    ('Edmund', 40, 5.9),
    ('Laura', 28, 5.7)
], dtype=dtype)


print("Original Structured Arrays:")
print(structured_array1)
print(structured_array2)

# Combine the two structured arrays into one
combined_array = np.concatenate((structured_array1, structured_array2))

# Print the combined structured array
print("\nCombined Structured Array:")
print(combined_array)

Output:

Original Structured Arrays:
[('Lehi', 25, 5.5) ('Albin', 30, 5.8)]
[('Zerach', 35, 6.1) ('Edmund', 40, 5.9) ('Laura', 28, 5.7)]

Combined Structured Array:
[('Lehi', 25, 5.5) ('Albin', 30, 5.8) ('Zerach', 35, 6.1)
 ('Edmund', 40, 5.9) ('Laura', 28, 5.7)]

Explanation:

• Import libraries:
• Imported numpy as "np" for array creation and manipulation.
• Define Data Type:
• Define the data type for the structured arrays 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 the First Structured Array:
• Created the first structured array structured_array1 using np.array(), providing sample data for two individuals.
• Create a Second Structured Array:
• Created the second structured array structured_array2 using np.array(), providing sample data for three individuals.
• Combine Structured Arrays:
• Combine the two structured arrays into one using "np.concatenate()".
• Print Combined Structured Array:
• Print the combined structured array to verify the result.

Python-Numpy Code Editor:

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