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*=======================================================================
*
* WCSLIB 8.5 - an implementation of the FITS WCS standard.
* Copyright (C) 1995-2025, Mark Calabretta
*
* This file is part of WCSLIB.
*
* WCSLIB is free software: you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* WCSLIB is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with WCSLIB. If not, see http://www.gnu.org/licenses.
*
* Author: Mark Calabretta, Australia Telescope National Facility, CSIRO.
* http://www.atnf.csiro.au/people/Mark.Calabretta
* $Id: twcs.f,v 8.5 2025/12/06 13:47:41 mcalabre Exp $
*=======================================================================
PROGRAM TWCS
*-----------------------------------------------------------------------
*
* TWCS1 tests WCSS2P and WCSP2S for closure on an oblique 2-D slice
* through a 4-D image with celestial, spectral and logarithmic
* coordinate axes.
*
*-----------------------------------------------------------------------
INCLUDE 'cel.inc'
INCLUDE 'prj.inc'
INCLUDE 'wcs.inc'
INCLUDE 'wcserr.inc'
INCLUDE 'wcsmath.inc'
DOUBLE PRECISION TOL
PARAMETER (TOL = 1D-10)
INTEGER NELEM
PARAMETER (NELEM = 9)
LOGICAL PASSED
INTEGER CHECK_ERROR, ETEST, I, J, K, LAT, LATIDX, LNG, LNGIDX,
: NFAIL(0:3), SPCIDX, STAT(0:360), STATUS, TEST_ERRORS
DOUBLE PRECISION FREQ, IMG(NELEM,0:360), LAT1, LNG1, PHI(0:360),
: PIXEL1(NELEM,0:360), PIXEL2(NELEM,0:360), R, RESID,
: RESMAX, THETA(0:360), TIME, WORLD1(NELEM,0:360),
: WORLD2(NELEM,0:360)
CHARACTER VERS*8
* On some systems, such as Sun Sparc, the struct MUST be aligned
* on a double precision boundary, done here using an equivalence.
* Failure to do this may result in mysterious "bus errors".
INTEGER WCS(WCSLEN)
DOUBLE PRECISION DUMMY
EQUIVALENCE (WCS,DUMMY)
* Number of axes.
INTEGER N
PARAMETER (N = 4)
* WCS header parameters.
INTEGER NAXIS, NPV, PVI(3), PVM(3)
DOUBLE PRECISION CDELT(N), CRPIX(N), CRVAL(N), LATPOLE, LONPOLE,
: PC(N,N), PV(3), RESTFRQ, RESTWAV
CHARACTER CTYPE(N)*72
COMMON /HEADER/ NAXIS, NPV, CRPIX, PC, CDELT, CRVAL, LONPOLE,
: LATPOLE, RESTFRQ, RESTWAV, PVI, PVM, PV
COMMON /HEADCH/ CTYPE
DATA NAXIS /N/
DATA (CRPIX(J), J=1,N)
: /513D0, 0D0, 0D0, 0D0/
DATA ((PC(I,J),J=1,N),I=1,N)
: /1.1D0, 0D0, 0D0, 0D0,
: 0D0, 1.0D0, 0D0, 0.1D0,
: 0D0, 0D0, 1.0D0, 0D0,
: 0D0, 0.2D0, 0D0, 1.0D0/
DATA (CDELT(I), I=1,N)
: /-9.635265432D-6, 1D0, 0.1D0, -1D0/
DATA (CTYPE(I), I=1,N)
: /'WAVE-F2W', 'XLAT-BON', 'TIME-LOG', 'XLON-BON'/
DATA (CRVAL(I), I=1,N)
: /0.214982042D0, -30D0, 1D0, 150D0/
DATA LONPOLE /150D0/
DATA LATPOLE /999D0/
DATA RESTFRQ /1.42040575D9/
DATA RESTWAV /0D0/
* Set PVi_m keyvalues for the longitude axis (I = 4). For test
* purposes, these are set so that the fiducial native coordinates
* are at the native pole, i.e. so that (phi0,theta0) = (0,90), but
* without any fiducial offset, i.e. iwith PVi_0a == 0 (by default).
DATA NPV /3/
DATA (PVI(K), PVM(K), PV(K), K=1,2)
: /4, 1, 0D0,
: 4, 2, 90D0/
* PVi_m keyvalues for the latitude axis (I = 2).
DATA PVI(3), PVM(3), PV(3)
: /2, 1, -30D0/
* For the wcserr tests.
COMMON /ERRTST/ ETEST
DATA ETEST /0/
*-----------------------------------------------------------------------
CALL WCSLIB_VERSION (VERS, 8)
WRITE (*, 10) VERS
10 FORMAT ('WCSLIB version number: ',A,/)
WRITE (*, 20)
20 FORMAT ('Testing closure of WCSLIB world coordinate ',
: 'transformation routines (twcs.f)',/,
: '-------------------------------------------',
: '--------------------------------',/)
* This routine simulates the actions of a FITS header parser.
STATUS = WCSPTI (WCS, WCS_FLAG, -1, 0, 0)
CALL PARSER (WCS)
* Test WCSENQ - note that the struct is unset.
NFAIL(0) = 0
IF (WCSENQ(WCS, WCSENQ_MEM).EQ.0) THEN
NFAIL(0) = 1
WRITE (*, 30)
30 FORMAT ('Unexpected result from WCSENQ: memory.')
END IF
* Put the struct in bypass mode (as a test).
STATUS = WCSPTI (WCS, WCS_FLAG, 1, 0, 0)
STATUS = WCSSET (WCS)
IF (STATUS.NE.0) THEN
WRITE (*, 40) STATUS
40 FORMAT ('WCSSET ERROR',I3)
END IF
* Test WCSENQ.
IF (WCSENQ(WCS, WCSENQ_SET + WCSENQ_BYP).EQ.0) THEN
NFAIL(0) = NFAIL(0) + 1
WRITE (*, 50)
50 FORMAT ('Unexpected result from WCSENQ: set and bypass.')
END IF
IF (WCSENQ(WCS, WCSENQ_CHK).EQ.0) THEN
NFAIL(0) = NFAIL(0) + 1
WRITE (*, 60) 'a'
60 FORMAT ('Unexpected result from WCSENQ: checksum (',A,').')
END IF
* Further test for WCSENQ - an inconsequential change.
STATUS = WCSPTD (WCS, WCS_LATPOLE, 999.001D0, 0, 0)
IF (WCSENQ(WCS, WCSENQ_CHK).EQ.1) THEN
NFAIL(0) = NFAIL(0) + 1
WRITE (*, 60) 'b'
END IF
IF (NFAIL(0).GT.0) WRITE (*, '()')
WRITE (*, 70) TOL
70 FORMAT ('Reporting tolerance',1PG8.1,' pixel.')
* Get indices.
STATUS = WCSGTI (WCS, WCS_LNG, LNGIDX)
STATUS = WCSGTI (WCS, WCS_LAT, LATIDX)
STATUS = WCSGTI (WCS, WCS_SPEC, SPCIDX)
* Initialize non-celestial world coordinates.
TIME = 1D0
FREQ = 1.42040595D9 - 180D0 * 62500D0
DO 80 K = 0, 360
WORLD1(1,K) = 0D0
WORLD1(2,K) = 0D0
WORLD1(3,K) = 0D0
WORLD1(4,K) = 0D0
WORLD1(3,K) = TIME
TIME = 1.01D0 * TIME
WORLD1(SPCIDX,K) = 2.99792458D8 / FREQ
FREQ = FREQ + 62500D0
80 CONTINUE
NFAIL(1) = 0
RESMAX = 0D0
DO 160 LAT = 90, -90, -1
LAT1 = DBLE(LAT)
K = 0
DO 90 LNG = -180, 180
LNG1 = DBLE(LNG)
WORLD1(LNGIDX,K) = LNG1
WORLD1(LATIDX,K) = LAT1
K = K + 1
90 CONTINUE
STATUS = WCSS2P (WCS, 361, NELEM, WORLD1, PHI, THETA, IMG,
: PIXEL1, STAT)
IF (STATUS.NE.0) THEN
WRITE (*, 100) STATUS, LAT1
100 FORMAT (3X,'WCSS2P(1) ERROR',I3,' (LAT1 =',F20.15, ')')
GO TO 160
END IF
STATUS = WCSP2S (WCS, 361, NELEM, PIXEL1, IMG, PHI, THETA,
: WORLD2, STAT)
IF (STATUS.NE.0) THEN
WRITE (*, 110) STATUS, LAT1
110 FORMAT (3X,'WCSP2S ERROR',I3,' (LAT1 =',F20.15, ')')
GO TO 160
END IF
STATUS = WCSS2P (WCS, 361, NELEM, WORLD2, PHI, THETA, IMG,
: PIXEL2, STAT)
IF (STATUS.NE.0) THEN
WRITE (*, 120) STATUS, LAT1
120 FORMAT (3X,'WCSS2P(2) ERROR',I3,' (LAT1 =',F20.15, ')')
GO TO 160
END IF
DO 150 K = 0, 360
RESID = 0D0
DO 130 I = 1, NAXIS
R = PIXEL2(I,K) - PIXEL1(I,K)
RESID = RESID + R*R
130 CONTINUE
RESID = SQRT(RESID)
IF (RESID.GT.RESMAX) RESMAX = RESID
IF (RESID.GT.TOL) THEN
NFAIL(1) = NFAIL(1) + 1
WRITE (*, 140) (WORLD1(I,K), I=1,NAXIS),
: (PIXEL1(I,K), I=1,NAXIS),
: (WORLD2(I,K), I=1,NAXIS),
: (PIXEL2(I,K), I=1,NAXIS)
140 FORMAT (/,'Closure error:',/,
: 'world1:',4F18.12,/,
: 'pixel1:',4F18.12,/,
: 'world2:',4F18.12,/,
: 'pixel2:',4F18.12)
END IF
LNG1 = LNG1 + 1D0
150 CONTINUE
160 CONTINUE
WRITE (*, 170) RESMAX
170 FORMAT ('WCSP2S/WCSS2P: Maximum closure residual =',1P,G8.1,
: ' pixel.')
* Test WCSERR.
WRITE (*, 180)
180 FORMAT (/,'IGNORE messages marked with ''OK'', they test ',
: 'WCSERR: ')
STATUS = WCSERR_ENABLE(1)
* Test 1 - take it out of bypass mode, so now WCSSET should fail.
STATUS = WCSPTD (WCS, WCS_PV, UNDEFINED, PVI(3), PVM(3))
STATUS = WCSPTI (WCS, WCS_FLAG, 0, 0, 0)
STATUS = WCSSET (WCS)
NFAIL(3) = CHECK_ERROR (WCS, STATUS, WCSERR_BAD_PARAM,
: 'Invalid parameter value')
NFAIL(3) = NFAIL(3) + TEST_ERRORS()
WRITE (*, '()')
PASSED = .TRUE.
IF (NFAIL(0).NE.0) THEN
PASSED = .FALSE.
WRITE (*, 190)
190 FORMAT ('FAIL: Unexpected result from WCSENQ.')
END IF
IF (NFAIL(1).NE.0) THEN
PASSED = .FALSE.
WRITE (*, 200) NFAIL(1)
200 FORMAT ('FAIL:',I5,' closure residuals exceed reporting ',
: 'tolerance.')
END IF
IF (NFAIL(3).NE.0) THEN
PASSED = .FALSE.
WRITE (*, 210) NFAIL(3)
210 FORMAT ('FAIL:',I5,' error messages differ from that ',
: 'expected.')
END IF
IF (PASSED) THEN
WRITE (*, 220)
220 FORMAT (
: 'PASS: All enquiry results returned as expected',/,
: 'PASS: All closure residuals are within reporting ',
: 'tolerance.',/,
: 'PASS: All error messages reported as expected.')
END IF
* Clean up.
STATUS = WCSFREE(WCS)
END
*-----------------------------------------------------------------------
SUBROUTINE PARSER (WCS)
*-----------------------------------------------------------------------
* In practice a parser would read the FITS header until it encountered
* the NAXIS keyword which must occur near the start, before any of the
* WCS keywords. It would then use WCSINI to allocate memory for arrays
* in the WCSPRM "data structure" and set default values.
*
* In this simulation the header keyvalues are set in the main program in
* variables passed in COMMON.
*-----------------------------------------------------------------------
* Number of axes.
INTEGER N
PARAMETER (N = 4)
INTEGER I, J, K, NAXIS, NPV, PVI(3), PVM(3), STATUS, WCS(*)
DOUBLE PRECISION CDELT(N), CRPIX(N), CRVAL(N), LATPOLE, LONPOLE,
: PC(N,N), PV(3), RESTFRQ, RESTWAV
CHARACTER CTYPE(N)*72
INCLUDE 'wcs.inc'
COMMON /HEADER/ NAXIS, NPV, CRPIX, PC, CDELT, CRVAL, LONPOLE,
: LATPOLE, RESTFRQ, RESTWAV, PVI, PVM, PV
COMMON /HEADCH/ CTYPE
*-----------------------------------------------------------------------
STATUS = WCSINI (NAXIS, WCS)
DO 20 I = 1, NAXIS
STATUS = WCSPTD (WCS, WCS_CRPIX, CRPIX(I), I, 0)
DO 10 J = 1, NAXIS
STATUS = WCSPTD (WCS, WCS_PC, PC(I,J), I, J)
10 CONTINUE
STATUS = WCSPTD (WCS, WCS_CDELT, CDELT(I), I, 0)
STATUS = WCSPTC (WCS, WCS_CTYPE, CTYPE(I), I, 0)
STATUS = WCSPTD (WCS, WCS_CRVAL, CRVAL(I), I, 0)
20 CONTINUE
STATUS = WCSPTD (WCS, WCS_LONPOLE, LONPOLE, 0, 0)
STATUS = WCSPTD (WCS, WCS_LATPOLE, LATPOLE, 0, 0)
STATUS = WCSPTD (WCS, WCS_RESTFRQ, RESTFRQ, 0, 0)
STATUS = WCSPTD (WCS, WCS_RESTWAV, RESTWAV, 0, 0)
DO 30 K = 1, NPV
STATUS = WCSPTD (WCS, WCS_PV, PV(K), PVI(K), PVM(K))
30 CONTINUE
END
*-----------------------------------------------------------------------
INTEGER FUNCTION TEST_ERRORS()
*-----------------------------------------------------------------------
CHARACTER NULL*1
PARAMETER (NULL = CHAR(0))
INTEGER CHECK_ERROR, ETEST, NFAIL, STATUS
CHARACTER CTYPE*72
* On some systems, such as Sun Sparc, the struct MUST be aligned
* on a double precision boundary, done here using an equivalence.
* Failure to do this may result in mysterious "bus errors".
INCLUDE 'wcs.inc'
INTEGER WCS(WCSLEN)
DOUBLE PRECISION DUMMY
EQUIVALENCE (WCS,DUMMY)
COMMON /ERRTST/ ETEST
*-----------------------------------------------------------------------
NFAIL = 0
* Test 2.
STATUS = WCSPTI (WCS, WCS_FLAG, -1, 0, 0)
STATUS = WCSINI (-32, WCS)
NFAIL = NFAIL + CHECK_ERROR (WCS, STATUS, WCSERR_MEMORY,
: 'naxis must not be negative (got -32)')
* Test 3.
STATUS = WCSPTI (WCS, WCS_FLAG, 0, 0, 0)
STATUS = WCSINI (2, WCS)
NFAIL = NFAIL + CHECK_ERROR (WCS, STATUS, WCSERR_SUCCESS, ' ')
* Test 4; CTYPE strings handled with CHARACTER*72 variable.
CTYPE = 'CUBEFACE'
STATUS = WCSPTC (WCS, WCS_CTYPE, CTYPE, 1, 0)
STATUS = WCSPTC (WCS, WCS_CTYPE, CTYPE, 2, 0)
STATUS = WCSSET (WCS)
NFAIL = NFAIL + CHECK_ERROR (WCS, STATUS, WCSERR_BAD_CTYPE,
: 'Multiple CUBEFACE axes (in CTYPE1 and CTYPE2)')
* Test 5; CTYPE strings handled C-style, i.e. with trailing '\0'.
STATUS = WCSPTI (WCS, WCS_FLAG, 0, 0, 0)
STATUS = WCSINI (2, WCS)
STATUS = WCSPTC (WCS, WCS_CTYPE, 'RA---FOO'//NULL, 1, 0)
STATUS = WCSPTC (WCS, WCS_CTYPE, 'DEC--BAR'//NULL, 2, 0)
STATUS = WCSSET (WCS)
NFAIL = NFAIL + CHECK_ERROR (WCS, STATUS, WCSERR_BAD_CTYPE,
: 'Unrecognized projection code (FOO in CTYPE1)')
* Test 6.
STATUS = WCSPTI (WCS, WCS_FLAG, 0, 0, 0)
STATUS = WCSINI (2, WCS)
STATUS = WCSPTC (WCS, WCS_CTYPE, 'RA---TAN'//NULL, 1, 0)
STATUS = WCSPTC (WCS, WCS_CTYPE, 'FREQ-LOG'//NULL, 2, 0)
STATUS = WCSSET (WCS)
NFAIL = NFAIL + CHECK_ERROR (WCS, STATUS, WCSERR_BAD_CTYPE,
: 'Unmatched celestial axes')
STATUS = WCSFREE(WCS)
TEST_ERRORS = NFAIL
END
*-----------------------------------------------------------------------
INTEGER FUNCTION CHECK_ERROR(WCS, STATUS, EXSTATUS, EXMSG)
*-----------------------------------------------------------------------
INCLUDE 'wcs.inc'
INCLUDE 'wcserr.inc'
INTEGER EXSTATUS, ILEN, ISTAT, ETEST, STATUS, WCS(WCSLEN)
CHARACTER ERRMSG*(WCSERR_MSG_LENGTH), EXMSG*(*)
* On some systems, such as Sun Sparc, the structs MUST be aligned
* on a double precision boundary. As a dummy argument, WCS should
* already be aligned. WCSERR is aligned here using an equivalence.
* Failure to do this may result in mysterious "bus errors".
INTEGER WCSERR(ERRLEN)
DOUBLE PRECISION DUMMY
EQUIVALENCE (WCSERR,DUMMY)
COMMON /ERRTST/ ETEST
*-----------------------------------------------------------------------
IF (STATUS.NE.0) THEN
ISTAT = WCSGTI (WCS, WCS_ERR, WCSERR(1))
ISTAT = WCSERR_GTC (WCSERR, WCSERR_MSG, ERRMSG)
ELSE
ERRMSG = ' '
END IF
ETEST = ETEST + 1
WRITE (*, 10) ETEST
10 FORMAT (/,'Test ',I2,'...')
IF (STATUS.EQ.EXSTATUS .AND. ERRMSG.EQ.EXMSG) THEN
CALL FLUSH(6)
ISTAT = WCSPERR (WCS, 'OK: '//CHAR(0))
WRITE (*, *) '...succeeded.'
CHECK_ERROR = 0
ELSE
WRITE (*, 20) EXSTATUS, EXMSG(:ILEN(EXMSG))
20 FORMAT ('Expected error ',I2,': ''',A,''', got')
CALL FLUSH(6)
ISTAT = WCSPERR (WCS, CHAR(0))
WRITE (*, *) '...failed.'
CHECK_ERROR = 1
END IF
END
*-----------------------------------------------------------------------
INTEGER FUNCTION ILEN(STRING)
*-----------------------------------------------------------------------
CHARACTER STRING*(*)
*-----------------------------------------------------------------------
DO 10 ILEN = LEN(STRING), 1, -1
IF (STRING(ILEN:ILEN).NE. ' ') RETURN
10 CONTINUE
ILEN = 0
END
|
