numpy.ma
MaskedArray.
unshare_mask
Copy the mask and set the sharedmask flag to False.
Whether the mask is shared between masked arrays can be seen from the sharedmask property. unshare_mask ensures the mask is not shared. A copy of the mask is only made if it was shared.
sharedmask
See also
numpy.ma.MaskedArray.soften_mask
numpy.ma.MaskedArray.shrink_mask