numpy.ma.masked_all_like

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
arrndarray

An array describing the shape and dtype of the required MaskedArray.

Returns
aMaskedArray

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')