numpy.ma.masked_all_like

numpy.ma.masked_all_like(arr) [source]

Empty masked array with the properties of an existing array.

Return an empty masked array of the same shape and dtype as the array arr, where all the data are masked.

Parameters:	arr : ndarray An array describing the shape and dtype of the required MaskedArray.
Returns:	a : MaskedArray A masked array with all data masked.
Raises:	AttributeError If arr doesn’t have a shape attribute (i.e. not an ndarray)

See also

masked_all

Empty masked array with all elements masked.

Examples

>>> import numpy.ma as ma
>>> arr = np.zeros((2, 3), dtype=np.float32)
>>> arr
array([[0., 0., 0.],
       [0., 0., 0.]], dtype=float32)
>>> ma.masked_all_like(arr)
masked_array(
  data=[[--, --, --],
        [--, --, --]],
  mask=[[ True,  True,  True],
        [ True,  True,  True]],
  fill_value=1e+20,
  dtype=float32)

The dtype of the masked array matches the dtype of arr.

>>> arr.dtype
dtype('float32')
>>> ma.masked_all_like(arr).dtype
dtype('float32')