numpy.ma.is_masked

numpy.ma.is_masked(x)

Determine whether input has masked values.

Accepts any object as input, but always returns False unless the input is a MaskedArray containing masked values.

Parameters:

x : array_like

Array to check for masked values.

Returns:

result : bool

True if x is a MaskedArray with masked values, False otherwise.

Examples

>>> import numpy.ma as ma
>>> x = ma.masked_equal([0, 1, 0, 2, 3], 0)
>>> x
masked_array(data=[--, 1, --, 2, 3],
             mask=[ True, False,  True, False, False],
       fill_value=0)
>>> ma.is_masked(x)
True
>>> x = ma.masked_equal([0, 1, 0, 2, 3], 42)
>>> x
masked_array(data=[0, 1, 0, 2, 3],
             mask=False,
       fill_value=42)
>>> ma.is_masked(x)
False

Always returns False if x isn’t a MaskedArray.

>>> x = [False, True, False]
>>> ma.is_masked(x)
False
>>> x = 'a string'
>>> ma.is_masked(x)
False