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numpy.ma.asarray

numpy.ma.asarray(a, dtype=None, order=None)

Convert the input to a masked array of the given data-type.

No copy is performed if the input is already an ndarray. If a is a subclass of MaskedArray, a base class MaskedArray is returned.

Parameters

aarray_like

Input data, in any form that can be converted to a masked array. This includes lists, lists of tuples, tuples, tuples of tuples, tuples of lists, ndarrays and masked arrays.

dtypedtype, optional

By default, the data-type is inferred from the input data.

order{‘C’, ‘F’}, optional

Whether to use row-major (‘C’) or column-major (‘FORTRAN’) memory representation. Default is ‘C’.

Returns

outMaskedArray

Masked array interpretation of a.

See also

asanyarray

Similar to asarray, but conserves subclasses.

Examples

>>>

>>> x = np.arange(10.).reshape(2, 5)
>>> x
array([[0., 1., 2., 3., 4.],
       [5., 6., 7., 8., 9.]])
>>> np.ma.asarray(x)
masked_array(
  data=[[0., 1., 2., 3., 4.],
        [5., 6., 7., 8., 9.]],
  mask=False,
  fill_value=1e+20)
>>> type(np.ma.asarray(x))
<class 'numpy.ma.core.MaskedArray'>