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|
include <imio.h>
include <imhdr.h>
include <mwset.h>
include "skywcs.h"
include "skywcsdef.h"
# SK_DECWCS -- Decode the wcs string which may be either an image name
# plus wcs, e.g. "dev$pix logical" or a string describing the celestial
# coordinate system, e.g. "J2000" or "galactic" into a celestial coordinate
# structure. If the input wcs is an image wcs then a non-NULL pointer to
# the image wcs structure is also returned. ERR is returned if a valid
# celestial coordinate structure cannot be created.
int procedure sk_decwcs (instr, mw, coo, imcoo)
char instr[ARB] #I the input wcs string
pointer mw #O the pointer to the image wcs structure
pointer coo #O the pointer to the coordinate structure
pointer imcoo #I pointer to an existing coordinate structure
int stat
pointer sp, str1, str2, laxno, paxval, im
int sk_strwcs(), sk_decim()
pointer immap()
errchk immap()
begin
call calloc (coo, LEN_SKYCOOSTRUCT, TY_STRUCT)
call strcpy (instr, SKY_COOSYSTEM(coo), SZ_FNAME)
# Allocate some working space.
call smark (sp)
call salloc (str1, SZ_LINE, TY_CHAR)
call salloc (str2, SZ_LINE, TY_CHAR)
call salloc (laxno, IM_MAXDIM, TY_INT)
call salloc (paxval, IM_MAXDIM, TY_INT)
# Decode the wcs.
call sscan (instr)
call gargwrd (Memc[str1], SZ_LINE)
call gargwrd (Memc[str2], SZ_LINE)
# First try to open an image wcs.
iferr {
im = immap (Memc[str1], READ_ONLY, 0)
# Decode the user wcs.
} then {
# Initialize.
mw = NULL
if (imcoo == NULL) {
SKY_NLNGAX(coo) = 2048
SKY_NLATAX(coo) = 2048
SKY_PLNGAX(coo) = 1
SKY_PLATAX(coo) = 2
SKY_XLAX(coo) = 1
SKY_YLAX(coo) = 2
SKY_VXOFF(coo) = 0.0d0
SKY_VYOFF(coo) = 0.0d0
SKY_VXSTEP(coo) = 1.0d0
SKY_VYSTEP(coo) = 1.0d0
SKY_WTYPE(coo) = 0
} else {
SKY_NLNGAX(coo) = SKY_NLNGAX(imcoo)
SKY_NLATAX(coo) = SKY_NLATAX(imcoo)
SKY_PLNGAX(coo) = SKY_PLNGAX(imcoo)
SKY_PLATAX(coo) = SKY_PLATAX(imcoo)
SKY_XLAX(coo) = SKY_XLAX(imcoo)
SKY_YLAX(coo) = SKY_YLAX(imcoo)
SKY_VXOFF(coo) = SKY_VXOFF(imcoo)
SKY_VYOFF(coo) = SKY_VYOFF(imcoo)
SKY_VXSTEP(coo) = SKY_VXSTEP(imcoo)
SKY_VYSTEP(coo) = SKY_VYSTEP(imcoo)
SKY_WTYPE(coo) = SKY_WTYPE(imcoo)
}
SKY_PIXTYPE(coo) = PIXTYPE_WORLD
# Decode the actual wcs.
stat = sk_strwcs (instr, SKY_CTYPE(coo), SKY_RADECSYS(coo),
SKY_EQUINOX(coo), SKY_EPOCH(coo))
switch (SKY_CTYPE(coo)) {
case CTYPE_EQUATORIAL:
SKY_NLNGUNITS(coo) = SKY_HOURS
SKY_NLATUNITS(coo) = SKY_DEGREES
default:
SKY_NLNGUNITS(coo) = SKY_DEGREES
SKY_NLATUNITS(coo) = SKY_DEGREES
}
# Decode the image wcs.
} else {
stat = sk_decim (im, Memc[str2], mw, coo)
call imunmap (im)
}
call sfree (sp)
SKY_STATUS(coo) = stat
return (stat)
end
# SK_DECWSTR -- Decode the wcs string coordinate system, e.g. "J2000" or
# "galactic" into a celestial coordinate structure. ERR is returned if a
# valid celestial coordinate structure cannot be created.
int procedure sk_decwstr (instr, coo, imcoo)
char instr[ARB] #I the input wcs string
pointer coo #O the pointer to the coordinate structure
pointer imcoo #I pointer to an existing coordinate structure
int stat
int sk_strwcs()
begin
call calloc (coo, LEN_SKYCOOSTRUCT, TY_STRUCT)
call strcpy (instr, SKY_COOSYSTEM(coo), SZ_FNAME)
# Initialize.
if (imcoo == NULL) {
SKY_NLNGAX(coo) = 2048
SKY_NLATAX(coo) = 2048
SKY_PLNGAX(coo) = 1
SKY_PLATAX(coo) = 2
SKY_XLAX(coo) = 1
SKY_YLAX(coo) = 2
SKY_VXOFF(coo) = 0.0d0
SKY_VYOFF(coo) = 0.0d0
SKY_VXSTEP(coo) = 1.0d0
SKY_VYSTEP(coo) = 1.0d0
SKY_WTYPE(coo) = 0
} else {
SKY_NLNGAX(coo) = SKY_NLNGAX(imcoo)
SKY_NLATAX(coo) = SKY_NLATAX(imcoo)
SKY_PLNGAX(coo) = SKY_PLNGAX(imcoo)
SKY_PLATAX(coo) = SKY_PLATAX(imcoo)
SKY_XLAX(coo) = SKY_XLAX(imcoo)
SKY_YLAX(coo) = SKY_YLAX(imcoo)
SKY_VXOFF(coo) = SKY_VXOFF(imcoo)
SKY_VYOFF(coo) = SKY_VYOFF(imcoo)
SKY_VXSTEP(coo) = SKY_VXSTEP(imcoo)
SKY_VYSTEP(coo) = SKY_VYSTEP(imcoo)
SKY_WTYPE(coo) = SKY_WTYPE(imcoo)
}
SKY_PIXTYPE(coo) = PIXTYPE_WORLD
# Decode the actual wcs.
stat = sk_strwcs (instr, SKY_CTYPE(coo), SKY_RADECSYS(coo),
SKY_EQUINOX(coo), SKY_EPOCH(coo))
switch (SKY_CTYPE(coo)) {
case CTYPE_EQUATORIAL:
SKY_NLNGUNITS(coo) = SKY_HOURS
SKY_NLATUNITS(coo) = SKY_DEGREES
default:
SKY_NLNGUNITS(coo) = SKY_DEGREES
SKY_NLATUNITS(coo) = SKY_DEGREES
}
SKY_STATUS(coo) = stat
return (stat)
end
# SK_DECIM -- Given an image descriptor and an image wcs string create a
# celstial coordinate structure. A non-NULL pointer to the image wcs structure
# is also returned. ERR is returned if a valid celestial coordinate descriptor
# cannot be created.
int procedure sk_decim (im, wcs, mw, coo)
pointer im #I the pointer to the input image
char wcs[ARB] #I the wcs string [logical|tv|physical|world]
pointer mw #O the pointer to the image wcs structure
pointer coo #O the pointer to the coordinate structure
int stat
pointer sp, str1, laxno, paxval
int sk_imwcs(), strdic(), mw_stati()
pointer mw_openim()
errchk mw_openim()
begin
call malloc (coo, LEN_SKYCOOSTRUCT, TY_STRUCT)
call sprintf (SKY_COOSYSTEM(coo), SZ_FNAME, "%s %s")
call pargstr (IM_HDRFILE(im))
call pargstr (wcs)
call smark (sp)
call salloc (str1, SZ_LINE, TY_CHAR)
call salloc (laxno, IM_MAXDIM, TY_INT)
call salloc (paxval, IM_MAXDIM, TY_INT)
# Try to open the image wcs.
iferr {
mw = mw_openim (im)
# Set up a dummy wcs.
} then {
#Initialize.
SKY_CTYPE(coo) = 0
SKY_RADECSYS(coo) = 0
SKY_EQUINOX(coo) = INDEFD
SKY_EPOCH(coo) = INDEFD
mw = NULL
SKY_PLNGAX(coo) = 1
SKY_PLATAX(coo) = 2
SKY_XLAX(coo) = 1
SKY_YLAX(coo) = 2
SKY_NLNGAX(coo) = 2048
SKY_NLATAX(coo) = 2048
SKY_VXOFF(coo) = 0.0d0
SKY_VYOFF(coo) = 0.0d0
SKY_VXSTEP(coo) = 1.0d0
SKY_VYSTEP(coo) = 1.0d0
SKY_WTYPE(coo) = 0
SKY_PIXTYPE(coo) = PIXTYPE_LOGICAL
SKY_NLNGUNITS(coo) = SKY_DEGREES
SKY_NLATUNITS(coo) = SKY_DEGREES
stat = ERR
# Decode the wcs.
} else {
SKY_PIXTYPE(coo) = strdic (wcs, Memc[str1], SZ_LINE, PIXTYPE_LIST)
if (SKY_PIXTYPE(coo) <= 0)
SKY_PIXTYPE(coo) = PIXTYPE_LOGICAL
if (sk_imwcs (im, mw, SKY_CTYPE(coo), SKY_PLNGAX(coo),
SKY_PLATAX(coo), SKY_WTYPE(coo), SKY_RADECSYS(coo),
SKY_EQUINOX(coo), SKY_EPOCH(coo)) == OK) {
switch (SKY_CTYPE(coo)) {
case CTYPE_EQUATORIAL:
SKY_NLNGUNITS(coo) = SKY_HOURS
SKY_NLATUNITS(coo) = SKY_DEGREES
default:
SKY_NLNGUNITS(coo) = SKY_DEGREES
SKY_NLATUNITS(coo) = SKY_DEGREES
}
call mw_gaxmap (mw, Memi[laxno], Memi[paxval], mw_stati(mw,
MW_NPHYSDIM))
if (Memi[laxno+SKY_PLNGAX(coo)-1] <
Memi[laxno+SKY_PLATAX(coo)-1]) {
SKY_XLAX(coo) = Memi[laxno+SKY_PLNGAX(coo)-1]
SKY_YLAX(coo) = Memi[laxno+SKY_PLATAX(coo)-1]
} else {
SKY_XLAX(coo) = Memi[laxno+SKY_PLATAX(coo)-1]
SKY_YLAX(coo) = Memi[laxno+SKY_PLNGAX(coo)-1]
}
if (SKY_XLAX(coo) <= 0 || SKY_YLAX(coo) <= 0) {
SKY_VXOFF(coo) = 0.0d0
SKY_VYOFF(coo) = 0.0d0
SKY_VXSTEP(coo) = 1.0d0
SKY_VYSTEP(coo) = 1.0d0
SKY_NLNGAX(coo) = 2048
SKY_NLATAX(coo) = 2048
stat = ERR
} else {
SKY_VXOFF(coo) = IM_VOFF(im,IM_VMAP(im,SKY_XLAX(coo)))
SKY_VYOFF(coo) = IM_VOFF(im,IM_VMAP(im,SKY_YLAX(coo)))
SKY_VXSTEP(coo) = IM_VSTEP(im,SKY_XLAX(coo))
SKY_VYSTEP(coo) = IM_VSTEP(im,SKY_YLAX(coo))
SKY_NLNGAX(coo) = IM_LEN(im,SKY_XLAX(coo))
SKY_NLATAX(coo) = IM_LEN(im,SKY_YLAX(coo))
stat = OK
}
} else {
call mw_close (mw)
mw = NULL
SKY_XLAX(coo) = 1
SKY_YLAX(coo) = 2
SKY_NLNGAX(coo) = 2048
SKY_NLATAX(coo) = 2048
SKY_VXOFF(coo) = 0.0d0
SKY_VYOFF(coo) = 0.0d0
SKY_VXSTEP(coo) = 1.0d0
SKY_VYSTEP(coo) = 1.0d0
SKY_NLNGUNITS(coo) = SKY_DEGREES
SKY_NLATUNITS(coo) = SKY_DEGREES
stat = ERR
}
}
call sfree (sp)
SKY_STATUS(coo) = stat
return (stat)
end
# SK_STRWCS -- Decode the sky coordinate system from an input string.
# The string syntax is [ctype] equinox [epoch]. The various options
# have been placed case statements. Although there is considerable
# duplication of code in the case statements, there are minor differences
# and I found it clearer to write it out rather than trying to be
# concise. I might want to clean this up a bit later.
int procedure sk_strwcs (instr, ctype, radecsys, equinox, epoch)
char instr[ARB] #I the input wcs string
int ctype #O the output coordinate type
int radecsys #O the output equatorial reference system
double equinox #O the output equinox
double epoch #O the output epoch of the observation
int ip, nitems, sctype, sradecsys, stat
pointer sp, str1, str2
int strdic(), nscan(), ctod()
double sl_ej2d(), sl_epb(), sl_eb2d(), sl_epj()
begin
# Initialize.
ctype = 0
radecsys = 0
equinox = INDEFD
epoch = INDEFD
# Allocate working space.
call smark (sp)
call salloc (str1, SZ_LINE, TY_CHAR)
call salloc (str2, SZ_LINE, TY_CHAR)
# Determine the coordinate string.
call sscan (instr)
call gargwrd (Memc[str1], SZ_LINE)
# Return with an error if the string is blank.
if (Memc[str1] == EOS || nscan() < 1) {
call sfree (sp)
return (ERR)
} else
nitems = 1
# If the coordinate type is undefined temporarily default it to
# equatorial.
sctype = strdic (Memc[str1], Memc[str2], SZ_LINE, FTYPE_LIST)
if (sctype <= 0) {
ctype = CTYPE_EQUATORIAL
} else {
switch (sctype) {
case FTYPE_FK4:
ctype = CTYPE_EQUATORIAL
radecsys = EQTYPE_FK4
case FTYPE_FK4NOE:
ctype = CTYPE_EQUATORIAL
radecsys = EQTYPE_FK4NOE
case FTYPE_FK5:
ctype = CTYPE_EQUATORIAL
radecsys = EQTYPE_FK5
case FTYPE_ICRS:
ctype = CTYPE_EQUATORIAL
radecsys = EQTYPE_ICRS
case FTYPE_GAPPT:
ctype = CTYPE_EQUATORIAL
radecsys = EQTYPE_GAPPT
case FTYPE_ECLIPTIC:
ctype = CTYPE_ECLIPTIC
case FTYPE_GALACTIC:
ctype = CTYPE_GALACTIC
case FTYPE_SUPERGALACTIC:
ctype = CTYPE_SUPERGALACTIC
}
call gargwrd (Memc[str1], SZ_LINE)
if (nscan() > nitems)
nitems = nitems + 1
}
sctype = ctype
sradecsys = radecsys
# Decode the coordinate system.
switch (sctype) {
# Decode the equatorial system, equinox, and epoch.
case CTYPE_EQUATORIAL:
switch (sradecsys) {
case EQTYPE_FK4, EQTYPE_FK4NOE:
if (Memc[str1] == 'J' || Memc[str1] == 'j' ||
Memc[str1] == 'B' || Memc[str1] == 'b')
ip = 2
else
ip = 1
if (ctod (Memc[str1], ip, equinox) <= 0)
equinox = 1950.0d0
if (Memc[str1] == 'J' || Memc[str1] == 'j')
equinox = sl_epb (sl_ej2d (equinox))
call gargwrd (Memc[str2], SZ_LINE)
if (nscan() <= nitems)
epoch = sl_eb2d (equinox)
else {
if (Memc[str2] == 'J' || Memc[str2] == 'j' ||
Memc[str2] == 'B' || Memc[str2] == 'b')
ip = 2
else
ip = 1
if (ctod (Memc[str2], ip, epoch) <= 0)
epoch = sl_eb2d (equinox)
else if (epoch <= 3000.0d0 && (Memc[str2] == 'J' ||
Memc[str2] == 'j'))
epoch = sl_ej2d (epoch)
else if (epoch > 3000.0d0)
epoch = epoch - 2400000.5d0
else
epoch = sl_eb2d (epoch)
}
case EQTYPE_FK5, EQTYPE_ICRS:
if (Memc[str1] == 'J' || Memc[str1] == 'j' ||
Memc[str1] == 'B' || Memc[str1] == 'b')
ip = 2
else
ip = 1
if (ctod (Memc[str1], ip, equinox) <= 0)
equinox = 2000.0d0
if (Memc[str1] == 'B' || Memc[str1] == 'b')
equinox = sl_epj(sl_eb2d (equinox))
call gargwrd (Memc[str2], SZ_LINE)
if (nscan() <= nitems)
epoch = sl_ej2d (equinox)
else {
if (Memc[str2] == 'J' || Memc[str2] == 'j' ||
Memc[str2] == 'B' || Memc[str2] == 'b')
ip = 2
else
ip = 1
if (ctod (Memc[str2], ip, epoch) <= 0)
epoch = sl_ej2d (equinox)
else if (epoch <= 3000.0d0 && (Memc[str2] == 'B' ||
Memc[str2] == 'b'))
epoch = sl_eb2d (epoch)
else if (epoch > 3000.0d0)
epoch = epoch - 2400000.5d0
else
epoch = sl_ej2d (epoch)
}
case EQTYPE_GAPPT:
equinox = 2000.0d0
if (Memc[str1] == 'J' || Memc[str1] == 'j' ||
Memc[str1] == 'B' || Memc[str1] == 'b')
ip = 2
else
ip = 1
if (ctod (Memc[str1], ip, epoch) <= 0) {
epoch = INDEFD
} else if (epoch <= 3000.0d0) {
if (Memc[str1] == 'B' || Memc[str1] == 'b')
epoch = sl_eb2d (epoch)
else if (Memc[str1] == 'J' || Memc[str1] == 'j')
epoch = sl_ej2d (epoch)
else if (epoch < 1984.0d0)
epoch = sl_eb2d (epoch)
else
epoch = sl_ej2d (epoch)
} else {
epoch = epoch - 2400000.5d0
}
default:
ip = 1
if (Memc[str1] == 'B' || Memc[str1] == 'b') {
radecsys = EQTYPE_FK4
ip = ip + 1
if (ctod (Memc[str1], ip, equinox) <= 0)
equinox = 1950.0d0
call gargwrd (Memc[str2], SZ_LINE)
if (nscan() <= nitems)
epoch = sl_eb2d (equinox)
else {
if (Memc[str2] == 'J' || Memc[str2] == 'j')
ip = 2
else if (Memc[str2] == 'B' || Memc[str2] == 'b')
ip = 2
else
ip = 1
if (ctod (Memc[str2], ip, epoch) <= 0)
epoch = sl_eb2d (equinox)
else if (epoch <= 3000.0d0 && (Memc[str2] == 'J' ||
Memc[str2] == 'j'))
epoch = sl_ej2d (epoch)
else if (epoch > 3000.0d0)
epoch = epoch - 2400000.5d0
else
epoch = sl_eb2d (epoch)
}
} else if (Memc[str1] == 'J' || Memc[str1] == 'j') {
radecsys = EQTYPE_FK5
ip = ip + 1
if (ctod (Memc[str1], ip, equinox) <= 0)
equinox = 2000.0d0
call gargwrd (Memc[str2], SZ_LINE)
if (nscan() <= nitems)
epoch = sl_ej2d (equinox)
else {
if (Memc[str2] == 'J' || Memc[str2] == 'j' ||
Memc[str2] == 'B' || Memc[str2] == 'b')
ip = 2
else
ip = 1
if (ctod (Memc[str2], ip, epoch) <= 0)
epoch = sl_ej2d (equinox)
else if (epoch <= 3000.0d0 && (Memc[str2] == 'B' ||
Memc[str2] == 'b'))
epoch = sl_eb2d (epoch)
else if (epoch > 3000.0d0)
epoch = epoch - 2400000.5d0
else
epoch = sl_ej2d (epoch)
}
} else if (ctod (Memc[str1], ip, equinox) <= 0) {
ctype = 0
radecsys = 0
equinox = INDEFD
epoch = INDEFD
} else if (equinox < 1984.0d0) {
radecsys = EQTYPE_FK4
call gargwrd (Memc[str2], SZ_LINE)
if (nscan() <= nitems)
epoch = sl_eb2d (equinox)
else {
if (Memc[str2] == 'J' || Memc[str2] == 'j' ||
Memc[str2] == 'B' || Memc[str2] == 'b')
ip = 2
else
ip = 1
if (ctod (Memc[str2], ip, epoch) <= 0)
epoch = sl_eb2d (equinox)
else if (epoch <= 3000.0d0 && (Memc[str2] == 'J' ||
Memc[str2] == 'j'))
epoch = sl_ej2d (epoch)
else if (epoch > 3000.0d0)
epoch = epoch - 2400000.5d0
else
epoch = sl_eb2d (epoch)
}
} else {
radecsys = EQTYPE_FK5
call gargwrd (Memc[str2], SZ_LINE)
if (nscan() <= nitems)
epoch = sl_ej2d (equinox)
else {
if (Memc[str2] == 'J' || Memc[str2] == 'j' ||
Memc[str2] == 'B' || Memc[str2] == 'b')
ip = 2
else
ip = 1
if (ctod (Memc[str2], ip, epoch) <= 0)
epoch = sl_ej2d (equinox)
else if (epoch <= 3000.0d0 && (Memc[str2] == 'B' ||
Memc[str2] == 'b'))
epoch = sl_eb2d (epoch)
else if (epoch > 3000.0d0)
epoch = epoch - 2400000.5d0
else
epoch = sl_ej2d (epoch)
}
}
}
# Decode the ecliptic coordinate system.
case CTYPE_ECLIPTIC:
if (Memc[str1] == 'J' || Memc[str1] == 'j' ||
Memc[str1] == 'B' || Memc[str1] == 'b')
ip = 2
else
ip = 1
if (ctod (Memc[str1], ip, epoch) <= 0) {
epoch = INDEFD
} else if (epoch <= 3000.0d0) {
if (Memc[str1] == 'B' || Memc[str1] == 'b')
epoch = sl_eb2d (epoch)
else if (Memc[str1] == 'J' || Memc[str1] == 'j')
epoch = sl_ej2d (epoch)
else if (epoch < 1984.0d0)
epoch = sl_eb2d (epoch)
else
epoch = sl_ej2d (epoch)
} else {
epoch = epoch - 2400000.5d0
}
# Decode the galactic and supergalactic coordinate system.
case CTYPE_GALACTIC, CTYPE_SUPERGALACTIC:
if (Memc[str1] == 'J' || Memc[str1] == 'j' ||
Memc[str1] == 'B' || Memc[str1] == 'b')
ip = 2
else
ip = 1
if (ctod (Memc[str1], ip, epoch) <= 0) {
epoch = sl_eb2d (1950.0d0)
} else if (epoch <= 3000.0d0) {
if (Memc[str1] == 'J' || Memc[str1] == 'j')
epoch = sl_ej2d (epoch)
else if (Memc[str1] == 'B' || Memc[str1] == 'b')
epoch = sl_eb2d (epoch)
else if (epoch < 1984.0d0)
epoch = sl_eb2d (epoch)
else
epoch = sl_ej2d (epoch)
} else {
epoch = epoch - 2400000.5d0
}
}
# Return the appropriate error status.
if (ctype == 0)
stat = ERR
else if (ctype == CTYPE_EQUATORIAL && (radecsys == 0 ||
IS_INDEFD(equinox) || IS_INDEFD(epoch)))
stat = ERR
else if (ctype == CTYPE_ECLIPTIC && IS_INDEFD(epoch))
stat = ERR
else
stat = OK
call sfree (sp)
return (stat)
end
# SK_IMWCS -- Decode the sky coordinate system of the image. Return
# an error if the sky coordinate system is not one of the supported types
# or required information is missing from the image header.
int procedure sk_imwcs (im, mw, ctype, lngax, latax, wtype, radecsys,
equinox, epoch)
pointer im #I the image pointer
pointer mw #I pointer to the world coordinate system
int ctype #O the output coordinate type
int lngax #O the output ra/glon/elon axis
int latax #O the output dec/glat/elat axis
int wtype #O the output projection type
int radecsys #O the output equatorial reference system
double equinox #O the output equinox
double epoch #O the output epoch of the observation
int i, ndim, axtype, day, month, year, ier, oldfits
pointer sp, atval
double hours
double imgetd(), sl_eb2d(), sl_ej2d()
int mw_stati(), strdic(), dtm_decode()
errchk mw_gwattrs(), imgstr(), imgetd()
begin
call smark (sp)
call salloc (atval, SZ_LINE, TY_CHAR)
# Initialize
ctype = 0
lngax = 0
latax = 0
wtype = 0
radecsys = 0
equinox = INDEFD
epoch = INDEFD
# Determine the sky coordinate system of the image.
ndim = mw_stati (mw, MW_NPHYSDIM)
do i = 1, ndim {
iferr (call mw_gwattrs (mw, i, "axtype", Memc[atval], SZ_LINE))
call strcpy ("INDEF", Memc[atval], SZ_LINE)
axtype = strdic (Memc[atval], Memc[atval], SZ_LINE, AXTYPE_LIST)
switch (axtype) {
case AXTYPE_RA, AXTYPE_DEC:
ctype = CTYPE_EQUATORIAL
case AXTYPE_ELON, AXTYPE_ELAT:
ctype = CTYPE_ECLIPTIC
case AXTYPE_GLON, AXTYPE_GLAT:
ctype = CTYPE_GALACTIC
case AXTYPE_SLON, AXTYPE_SLAT:
ctype = CTYPE_SUPERGALACTIC
default:
;
}
switch (axtype) {
case AXTYPE_RA, AXTYPE_ELON, AXTYPE_GLON, AXTYPE_SLON:
lngax = i
case AXTYPE_DEC, AXTYPE_ELAT, AXTYPE_GLAT, AXTYPE_SLAT:
latax = i
default:
;
}
}
# Return if the sky coordinate system cannot be decoded.
if (ctype == 0 || lngax == 0 || latax == 0) {
call sfree (sp)
return (ERR)
}
# Decode the sky projection.
iferr {
call mw_gwattrs (mw, lngax, "wtype", Memc[atval], SZ_LINE)
} then {
iferr (call mw_gwattrs(mw, latax, "wtype", Memc[atval], SZ_LINE))
call strcpy ("linear", Memc[atval], SZ_LINE)
}
wtype = strdic (Memc[atval], Memc[atval], SZ_LINE, WTYPE_LIST)
# Return if the sky projection system is not supported.
if (wtype == 0) {
call sfree (sp)
return (ERR)
}
# Determine the RA/DEC system and equinox.
if (ctype == CTYPE_EQUATORIAL) {
# Get the equinox of the coordinate system. The EQUINOX keyword
# takes precedence over EPOCH.
iferr {
equinox = imgetd (im, "EQUINOX")
} then {
iferr {
equinox = imgetd (im, "EPOCH")
} then {
equinox = INDEFD
}
}
# Determine which equatorial system will be used. The default
# is FK4 if equinox < 1984.0, FK5 if equinox is >= 1984.
iferr {
call imgstr (im, "RADECSYS", Memc[atval], SZ_LINE)
} then {
radecsys = 0
} else {
call strlwr (Memc[atval])
radecsys = strdic (Memc[atval], Memc[atval], SZ_LINE,
EQTYPE_LIST)
}
if (radecsys == 0) {
if (IS_INDEFD(equinox))
radecsys = EQTYPE_FK5
else if (equinox < 1984.0d0)
radecsys = EQTYPE_FK4
else
radecsys = EQTYPE_FK5
}
# Get the MJD of the observation. If there is no MJD in the
# header use the DATE_OBS keyword value and transform it to
# an MJD.
iferr {
epoch = imgetd (im, "MJD-WCS")
} then {
iferr {
epoch = imgetd (im, "MJD-OBS")
} then {
iferr {
call imgstr (im, "DATE-OBS", Memc[atval], SZ_LINE)
} then {
epoch = INDEFD
} else if (dtm_decode (Memc[atval], year, month, day,
hours, oldfits) == OK) {
call sl_cadj (year, month, day, epoch, ier)
if (ier != 0)
epoch = INDEFD
else if (! IS_INDEFD(hours) && hours >= 0.0d0 &&
hours <= 24.0d0)
epoch = epoch + hours / 24.0d0
} else
epoch = INDEFD
}
}
# Set the default equinox and epoch appropriate for each
# equatorial system if these are undefined.
switch (radecsys) {
case EQTYPE_FK4, EQTYPE_FK4NOE:
if (IS_INDEFD(equinox))
equinox = 1950.0d0
if (IS_INDEFD(epoch))
epoch = sl_eb2d (1950.0d0)
case EQTYPE_FK5, EQTYPE_ICRS:
if (IS_INDEFD(equinox))
equinox = 2000.0d0
if (IS_INDEFD(epoch))
epoch = sl_ej2d (2000.0d0)
case EQTYPE_GAPPT:
equinox = 2000.0d0
;
}
# Return if the epoch is undefined. This can only occur if
# the equatorial coordinate system is GAPPT and there is NO
# epoch of observation in the image header.
if (IS_INDEFD(epoch)) {
call sfree (sp)
return (ERR)
}
}
# Get the MJD of the observation. If there is no MJD in the
# header use the DATE_OBS keyword value and transform it to
# an MJD.
if (ctype == CTYPE_ECLIPTIC) {
iferr {
epoch = imgetd (im, "MJD-WCS")
} then {
iferr {
epoch = imgetd (im, "MJD-OBS")
} then {
iferr {
call imgstr (im, "DATE-OBS", Memc[atval], SZ_LINE)
} then {
epoch = INDEFD
} else if (dtm_decode (Memc[atval], year, month, day,
hours, oldfits) == OK) {
call sl_cadj (year, month, day, epoch, ier)
if (ier != 0)
epoch = INDEFD
else if (! IS_INDEFD(hours) && hours >= 0.0d0 &&
hours <= 24.0d0)
epoch = epoch + hours / 24.0d0
} else
epoch = INDEFD
}
}
# Return if the epoch is undefined.
if (IS_INDEFD(epoch)) {
call sfree (sp)
return (ERR)
}
}
if (ctype == CTYPE_GALACTIC || ctype == CTYPE_SUPERGALACTIC) {
# Get the MJD of the observation. If there is no MJD in the
# header use the DATE_OBS keyword value and transform it to
# an MJD.
iferr {
epoch = imgetd (im, "MJD-WCS")
} then {
iferr {
epoch = imgetd (im, "MJD-OBS")
} then {
iferr {
call imgstr (im, "DATE-OBS", Memc[atval], SZ_LINE)
} then {
epoch = sl_eb2d (1950.0d0)
} else if (dtm_decode (Memc[atval], year, month, day,
hours, oldfits) == OK) {
call sl_cadj (year, month, day, epoch, ier)
if (ier != 0)
epoch = sl_eb2d (1950.0d0)
else {
if (! IS_INDEFD(hours) && hours >= 0.0d0 &&
hours <= 24.0d0)
epoch = epoch + hours / 24.0d0
#if (epoch < 1984.0d0)
#epoch = sl_eb2d (epoch)
#else
#epoch = sl_ej2d (epoch)
}
} else
epoch = sl_eb2d (1950.0d0)
}
}
}
call sfree (sp)
return (OK)
end
# SK_ENWCS -- Encode the celestial wcs system.
procedure sk_enwcs (coo, wcsstr, maxch)
pointer coo #I the celestial coordinate system descriptor
char wcsstr[ARB] #O the output wcs string
int maxch #I the size of the output string
double sk_statd(), sl_epj(), sl_epb()
int sk_stati()
begin
switch (sk_stati (coo, S_CTYPE)) {
case CTYPE_EQUATORIAL:
switch (sk_stati(coo, S_RADECSYS)) {
case EQTYPE_GAPPT:
if (IS_INDEFD(sk_statd(coo, S_EPOCH))) {
call sprintf (wcsstr, maxch, "apparent")
} else {
call sprintf (wcsstr, maxch, "apparent J%0.8f")
call pargd (sl_epj(sk_statd(coo, S_EPOCH)))
}
case EQTYPE_FK5:
call sprintf (wcsstr, maxch, "fk5 J%0.3f J%0.8f")
call pargd (sk_statd(coo, S_EQUINOX))
call pargd (sl_epj(sk_statd(coo, S_EPOCH)))
case EQTYPE_ICRS:
call sprintf (wcsstr, maxch, "icrs J%0.3f J%0.8f")
call pargd (sk_statd(coo, S_EQUINOX))
call pargd (sl_epj(sk_statd(coo, S_EPOCH)))
case EQTYPE_FK4:
call sprintf (wcsstr, maxch, "fk4 B%0.3f B%0.8f")
call pargd (sk_statd(coo, S_EQUINOX))
call pargd (sl_epb(sk_statd(coo, S_EPOCH)))
case EQTYPE_FK4NOE:
call sprintf (wcsstr, maxch, "fk4noe B%0.3f B%0.8f")
call pargd (sk_statd(coo, S_EQUINOX))
call pargd (sl_epb(sk_statd(coo, S_EPOCH)))
default:
wcsstr[1] = EOS
}
case CTYPE_ECLIPTIC:
if (IS_INDEFD(sk_statd(coo, S_EPOCH))) {
call sprintf (wcsstr, maxch, "ecliptic")
} else {
call sprintf (wcsstr, maxch, "ecliptic J%0.8f")
call pargd (sl_epj(sk_statd(coo, S_EPOCH)))
}
case CTYPE_GALACTIC:
call sprintf (wcsstr, maxch, "galactic J%0.8f")
call pargd (sl_epj(sk_statd(coo, S_EPOCH)))
case CTYPE_SUPERGALACTIC:
call sprintf (wcsstr, maxch, "supergalactic j%0.8f")
call pargd (sl_epj(sk_statd(coo, S_EPOCH)))
}
end
# SK_COPY -- Copy the coodinate structure.
pointer procedure sk_copy (cooin)
pointer cooin #I the pointer to the input structure
pointer cooout
begin
if (cooin == NULL)
cooout = NULL
else {
call calloc (cooout, LEN_SKYCOOSTRUCT, TY_STRUCT)
SKY_VXOFF(cooout) = SKY_VXOFF(cooin)
SKY_VYOFF(cooout) = SKY_VYOFF(cooin)
SKY_VXSTEP(cooout) = SKY_VXSTEP(cooin)
SKY_VYSTEP(cooout) = SKY_VYSTEP(cooin)
SKY_EQUINOX(cooout) = SKY_EQUINOX(cooin)
SKY_EPOCH(cooout) = SKY_EPOCH(cooin)
SKY_CTYPE(cooout) = SKY_CTYPE(cooin)
SKY_RADECSYS(cooout) = SKY_RADECSYS(cooin)
SKY_WTYPE(cooout) = SKY_WTYPE(cooin)
SKY_PLNGAX(cooout) = SKY_PLNGAX(cooin)
SKY_PLATAX(cooout) = SKY_PLATAX(cooin)
SKY_XLAX(cooout) = SKY_XLAX(cooin)
SKY_YLAX(cooout) = SKY_YLAX(cooin)
SKY_PIXTYPE(cooout) = SKY_PIXTYPE(cooin)
SKY_NLNGAX(cooout) = SKY_NLNGAX(cooin)
SKY_NLATAX(cooout) = SKY_NLATAX(cooin)
SKY_NLNGUNITS(cooout) = SKY_NLNGUNITS(cooin)
SKY_NLATUNITS(cooout) = SKY_NLATUNITS(cooin)
call strcpy (SKY_COOSYSTEM(cooin), SKY_COOSYSTEM(cooout),
SZ_FNAME)
}
return (cooout)
end
# SK_CLOSE -- Free the coordinate structure.
procedure sk_close (coo)
pointer coo #U the input coordinate structure
begin
if (coo != NULL)
call mfree (coo, TY_STRUCT)
end
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