skycoord_to_lmn

skycoord_to_lmn(pos: astropy.coordinates.sky_coordinate.SkyCoord, phasecentre: astropy.coordinates.sky_coordinate.SkyCoord)

Convert astropy sky coordinates into the l,m,n coordinate system relative to a phase centre.

The l,m,n is a RHS coordinate system with * its origin on the sky sphere * m,n and the celestial north on the same plane * l,m a tangential plane of the sky sphere

Note that this means that l increases east-wards