@frame_transform_graph.transform(coord.StaticMatrixTransform, coord.Galactic, Sagittarius)
def galactic_to_sgr():
 return SGR_MATRIX

@ frame_transform_graph . transform ( coord . StaticMatrixTransform , coord . Galactic , Sagittarius ) def galactic_to_sgr ( ) : return SGR_MATRIX
compute the transformation matrix from galactic spherical to heliocentric sgr coordinates .