'Store information about some default, pre-defined transformation
equations.
Parameters
curv_coord_name : str
The type of the new coordinate system.'

def _set_transformation_equations_mapping(self, curv_coord_name):

    equations_mapping = {'cartesian': (self.x, self.y, self.z), 'spherical': (((self.x * sin(self.y)) * cos(self.z)), ((self.x * sin(self.y)) * sin(self.z)), (self.x * cos(self.y))), 'cylindrical': ((self.x * cos(self.y)), (self.x * sin(self.y)), self.z)}
    if (curv_coord_name not in equations_mapping):
        raise ValueError('Wrong    set    of    parameters.Type    of    coordinate    system    is    defined')
    self._transformation_eqs = equations_mapping[curv_coord_name]
