numpy.isreal

numpy.isreal(x)

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

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

Parameters:

xarray_like

Input array.

Returns:

outndarray, bool

Boolean array of same shape as x.

See also

iscomplex

isrealobj

Return True if x is not a complex type.

Notes

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

Examples

>>> 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])