numpy.isreal — NumPy v2.2 Manual (original) (raw)

numpy.isreal(x)[source]#

Returns a bool array, where True if input element is real.

If element has complex type with zero imaginary part, the return value for that element is True.

Parameters:

xarray_like

Input array.

Returns:

outndarray, bool

Boolean array of same shape as x.

Notes

isreal may behave unexpectedly for string or object arrays (see examples)

Examples

import numpy as np a = np.array([1+1j, 1+0j, 4.5, 3, 2, 2j], dtype=complex) np.isreal(a) array([False, True, True, True, True, False])

The function does not work on string arrays.

a = np.array([2j, "a"], dtype="U") np.isreal(a) # Warns about non-elementwise comparison False

Returns True for all elements in input array of dtype=object even if any of the elements is complex.

a = np.array([1, "2", 3+4j], dtype=object) np.isreal(a) array([ True, True, True])

isreal should not be used with object arrays

a = np.array([1+2j, 2+1j], dtype=object) np.isreal(a) array([ True, True])