Method _collapse

numpy/matrixlib/defmatrix.py:254–261

A convenience function for operations that want to collapse to a scalar like _align, but are using keepdims=True

(self, axis)

            raise ValueError("unsupported axis")

    def _collapse(self, axis):
        """A convenience function for operations that want to collapse
        to a scalar like _align, but are using keepdims=True
        """
        if axis is None:
            return self[0, 0]
        else:
            return self

    # Necessary because base-class tolist expects dimension
    #  reduction by x[0]