IsNan

Description

IsNan classifies each input element: outputs 1.0 when the input is NaN, and 0.0 for any finite or infinite value.

Unlike most screamer functions, IsNan does not propagate NaN; instead, it converts NaN into a definite 1.0 flag. This makes it useful for building masks that mark missing data positions before passing them to Where or other logic operators.

Parameters: IsNan takes no parameters.

Examples

Usage example

import numpy as np
from screamer import IsNan

x = np.array([1.0, np.nan, 3.0, np.nan, 5.0])
print(IsNan()(x))     # -> [0. 1. 0. 1. 0.]  (1.0 where the input is NaN)

[0. 1. 0. 1. 0.]