numpy.ma.make_mask_none

numpy.ma.make_mask_none(newshape, dtype=None)

Return a boolean mask of the given shape, filled with False.

This function returns a boolean ndarray with all entries False, that can be used in common mask manipulations. If a complex dtype is specified, the type of each field is converted to a boolean type.

Parameters :

newshape : tuple

A tuple indicating the shape of the mask.

dtype: {None, dtype}, optional :

If None, use a MaskType instance. Otherwise, use a new datatype with the same fields as dtype, converted to boolean types.

Returns :

result : ndarray

An ndarray of appropriate shape and dtype, filled with False.

See also

make_mask

Create a boolean mask from an array.

make_mask_descr

Construct a dtype description list from a given dtype.

Examples

>>> import numpy.ma as ma
>>> ma.make_mask_none((3,))
array([False, False, False], dtype=bool)

Defining a more complex dtype.

>>> dtype = np.dtype({'names':['foo', 'bar'],
                      'formats':[np.float32, np.int]})
>>> dtype
dtype([('foo', '<f4'), ('bar', '<i4')])
>>> ma.make_mask_none((3,), dtype=dtype)
array([(False, False), (False, False), (False, False)],
      dtype=[('foo', '|b1'), ('bar', '|b1')])