'Store information about Lame coefficient, for pre-defined
curvilinear coordinate systems. Return tuple with scaling
factor.
Parameters
curv_coord_name : str
The type of the new coordinate system.'

def _set_lame_coefficient_mapping(self, curv_coord_name):

    coefficient_mapping = {'cartesian': (1, 1, 1), 'spherical': (1, self.x, (self.x * sin(self.y))), 'cylindrical': (1, self.y, 1)}
    if (curv_coord_name not in coefficient_mapping):
        raise ValueError('Wrong    set    of    parameters.    Type    of    coordinate    system    is    not    defined')
    (self._h1, self._h2, self._h3) = coefficient_mapping[curv_coord_name]
