NumPy: Change the sign of a given array to that of a given array, element-wise
Write a NumPy program to change the sign of a given array to that of a given array, element-wise.
Sample Solution:
Python Code:
# Importing the NumPy library
import numpy as np
# Creating an array with integer values from -1 to 2
x1 = np.array([-1, 0, 1, 2])
# Displaying the original array x1
print("Original array: ")
print(x1)
# Assigning a floating-point value to x2
x2 = -2.1
# Displaying the sign of x1 with respect to x2, element-wise using np.copysign()
print("\nSign of x1 to that of x2, element-wise:")
print(np.copysign(x1, x2))
Sample Output:
Original array: [-1 0 1 2] Sign of x1 to that of x2, element-wise: [-1. -0. -1. -2.]
Explanation:
x1 = np.array([-1, 0, 1, 2]): x1 is a 1-dimensional NumPy array of integers, with the values [-1, 0, 1, 2].
x2 = -2.1: x2 is a scalar value of type float.
np.copysign(x1, x2): This code returns an array with the same magnitude as x1, but with the sign of x2, which is negative. Therefore, the output will be array([-1. -0. -1. -2.]), which is an array with the same magnitude as x1, but with the sign changed to negative.
Python-Numpy Code Editor: