From 40e5a5811c6ffce9b0974e93cdd927cbcf60c157 Mon Sep 17 00:00:00 2001 From: Joe Hunkeler Date: Tue, 11 Aug 2015 16:51:37 -0400 Subject: Repatch (from linux) of OSX IRAF --- math/slalib/doc/precss.hlp | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 math/slalib/doc/precss.hlp (limited to 'math/slalib/doc/precss.hlp') diff --git a/math/slalib/doc/precss.hlp b/math/slalib/doc/precss.hlp new file mode 100644 index 00000000..ab244cf5 --- /dev/null +++ b/math/slalib/doc/precss.hlp @@ -0,0 +1,44 @@ +.help precss Jun99 "Slalib Package" +.nf + + SUBROUTINE slPRCS (SYSTEM, EP0, EP1, RA, DC) + + - - - - - - - + P R C E + - - - - - - - + + Precession - either FK4 (Bessel-Newcomb, pre IAU 1976) or + FK5 (Fricke, post IAU 1976) as required. + + Given: + SYSTEM int precession to be applied: 1 = FK4 or 2 = FK5 + EP0,EP1 dp starting and ending epoch + RA,DC dp RA,Dec, mean equator & equinox of epoch EP0 + + Returned: + RA,DC dp RA,Dec, mean equator & equinox of epoch EP1 + + Called: slDA2P, slPRBN, slPREC, slDS2C, + slDMXV, slDC2S + + Notes: + + 1) Lowercase characters in SYSTEM are acceptable. + + 2) The epochs are Besselian if SYSTEM=FK4 and Julian if FK5. + For example, to precess coordinates in the old system from + equinox 1900.0 to 1950.0 the call would be: + CALL slPRCS (1, 1900D0, 1950D0, RA, DC) + + 3) This routine will NOT correctly convert between the old and + the new systems - for example conversion from B1950 to J2000. + For these purposes see slFK45, slFK54, slF45Z and + slF54Z. + + 4) If an invalid SYSTEM is supplied, values of -99D0,-99D0 will + be returned for both RA and DC. + + P.T.Wallace Starlink 20 April 1990 + +.fi +.endhelp -- cgit