[fitswcs] inherit vs. concatenate

[Eric Greisen]

Steve Allen writes:
 > On Tue 2002-01-15T21:03:00 -1000, Malcolm J. Currie hath writ:
 > >                                             The main question for
 > > the Michelle headers is whether or not the PC matrix is here to stay.
 > 
 > We have an instrument now being dismantled for shipment to Mauna Kea.
 > Even though there is still time to change the image acquistion
 > software we have decided that DEIMOS will use the CDj_i matrix.
 > The current drafts make it clear that we are perfectly safe
 > doing so.

So long as you do not want to male a Paper IV correction following the
multiplication by CD.  In that case you will have units probelms - in
principle they are just floating keyword values but they will be more
difficult to implement and differ vastly from Paper IV corrections
made before the PC/CD.

Eric Greisen

 > 
 > 
 > 
 > --
 > Steve Allen          UCO/Lick Observatory       Santa Cruz, CA 95064
 > sla at ucolick.org      Voice: +1 831 459 3046     http://www.ucolick.org/~sla
 > PGP: 1024/E46978C5   F6 78 D1 10 62 94 8F 2E    49 89 0E FE 26 B4 14 93
 > _______________________________________________
 > fitswcs mailing list
 > fitswcs at listmgr.cv.nrao.edu
 > http://listmgr.cv.nrao.edu/mailman/listinfo/fitswcs
 >