How to mask an array outside a given interval in NumPy

Overview

In NumPy, the masked_outside() function is used to mask an array outside a given interval.

Syntax

ma.masked_outside(x, v1, v2)
Syntax for the masked_outside() function

Parameters

This function takes the following parameter values:

  • x: This is the input array.
  • v1 and v2 : These represent the boundary for which the values of the given array are not to be masked. Both values—v1 and v2—are not included when masking.

Return value

This function returns a masked array with values within the specified intervals masked.

Example

# A code to illustrate the masked_inside() function
# importing the necessary libraries
import numpy as np
import numpy.ma as ma
# creating an input array
my_array = np.array([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
# masking the values outside 3 to 7
mask_array =ma.masked_outside(my_array, 3, 7)
print(mask_array)

Explanation

  • Line 4–5: We import the necessary library and module.
  • Line 8: We create an input array, my_array.
  • Line 11: We mask the values outside the interval of 37 in the input array using the masked_outside() function. The result is assigned to a variable, mask_array.
  • Line 13: We print the value of the masked array, mask_array.

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