NumPy: Test comparison operators

NumPy String: Exercise-14 with Solution

Write a NumPy program to test equal, not equal, greater equal, greater and less test of all the elements of two given arrays.

Sample Solution:

Python Code:

# Importing necessary library
import numpy as np

# Creating two NumPy arrays containing strings
x1 = np.array(['Hello', 'PHP', 'JS', 'examples', 'html'], dtype=np.str)
x2 = np.array(['Hello', 'php', 'Java', 'examples', 'html'], dtype=np.str)

# Displaying the content of Array1
print("\nArray1:")
print(x1)

# Displaying the content of Array2
print("Array2:")
print(x2)

# Comparing the strings in x1 and x2 element-wise for equality
print("\nEqual test:")
r = np.char.equal(x1, x2)
print(r)

# Comparing the strings in x1 and x2 element-wise for inequality
print("\nNot equal test:")
r = np.char.not_equal(x1, x2)
print(r)

# Comparing the strings in x1 and x2 element-wise to check if x1 is less than or equal to x2
print("\nLess equal test:")
r = np.char.less_equal(x1, x2)
print(r)

# Comparing the strings in x1 and x2 element-wise to check if x1 is greater than or equal to x2
print("\nGreater equal test:")
r = np.char.greater_equal(x1, x2)
print(r)

# Comparing the strings in x1 and x2 element-wise to check if x1 is less than x2
print("\nLess test:")
r = np.char.less(x1, x2)
print(r) 

Sample Input:

['Hello' 'PHP' 'JS' 'examples' 'html']

['Hello' 'php' 'Java' 'examples' 'html']

Sample Output:

Array1:
['Hello' 'PHP' 'JS' 'examples' 'html']
Array2:
['Hello' 'php' 'Java' 'examples' 'html']

Equal test:
[ True False False  True  True]

Not equal test:
[False  True  True False False]

Less equal test:
[ True  True  True  True  True]

Greater equal test:
[ True False False  True  True]

Less test:
[False  True  True False False]

Explanation:

In the above code –

x1 = np.array(['Hello', 'PHP', 'JS', 'examples', 'html'], dtype=np.str): x1 is a NumPy array containing string data.

x2 = np.array(['Hello', 'php', 'Java', 'examples', 'html'], dtype=np.str): x2 is a NumPy array containing string data.

np.char.equal(x1, x2): This code compares element-wise if two arrays have the same strings at corresponding positions. It returns a boolean array of the same shape as inputs.

np.char.not_equal(x1, x2): This code is similar to equal function, but returns the opposite of equal function.

np.char.less_equal(x1, x2): This code returns a boolean array of the same shape as inputs, where each element is True if x1 is less than or equal to x2.

np.char.greater_equal(x1, x2): This code returns a boolean array of the same shape as inputs, where each element is True if x1 is greater than or equal to x2.

np.char.less(x1, x2): This code returns a boolean array of the same shape as inputs, where each element is True if x1 is less than x2.

Pictorial Presentation:

Python-Numpy Code Editor:

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