numpy.ma.MaskedArray.__isub__
method
- 
MaskedArray.__isub__(other)[source]
- 
Subtract other from self in-place. 
    © 2005–2019 NumPy Developers
Licensed under the 3-clause BSD License.
    https://docs.scipy.org/doc/numpy-1.16.1/reference/generated/numpy.ma.MaskedArray.__isub__.html