(self, scalar_field)
return self._v1(self._v2(scalar_field)) - self._v2(self._v1(scalar_field))
Apply on a scalar field.

        If the argument is not a scalar field an error is raised.
Apply on a scalar field.
Apply on a scalar field .
def __call__(self, scalar_field):
        """Apply on a scalar field.

        If the argument is not a scalar field an error is raised.
        """
        return self._v1(self._v2(scalar_field)) - self._v2(self._v1(scalar_field))
def __call__ ( self , scalar_field ) : return self . _v1 ( self . _v2 ( scalar_field ) ) - self . _v2 ( self . _v1 ( scalar_field ) )