[gnuastro-commits] master 06f72e6: Library (wcs.h): correcting for unrecognized angstroms units

[Mohammad Akhlaghi]

branch: master
commit 06f72e6ad06f13efef90902ddefd879f00170598
Author: Mohammad Akhlaghi <mohammad@akhlaghi.org>
Commit: Mohammad Akhlaghi <mohammad@akhlaghi.org>

    Library (wcs.h): correcting for unrecognized angstroms units
    
    Until now, immediately after reading the WCS structure from the file
    header, we would pass it to WCSLIB's 'wcsfix' function. However, this
    function doesn't recognize the 'angstroms' units, only 'angstrom' (note the
    differing 's')! As a result, it would hit a segmentation fault within
    WCSLIB and the program would crash.
    
    With this commit, we now check the value to the 'CUNIT3' keyword. If its
    value is 'angstroms' (not case sensitive), we manually remove the 's' and
    this fixes the issue in WCSLIB.
    
    This issue was found with the help of Alireza Molaeinezhad.
---
 THANKS                       |  3 ++-
 doc/announce-acknowledge.txt |  1 +
 lib/wcs.c                    | 47 +++++++++++++++++++++++++++++++++-----------
 3 files changed, 39 insertions(+), 12 deletions(-)

diff --git a/THANKS b/THANKS
index 69d1ca7..d341069 100644
--- a/THANKS
+++ b/THANKS
@@ -64,9 +64,10 @@ support in Gnuastro. The list is ordered alphabetically (by 
family name).
     Sebastián Luna Valero                sluna@iaa.es
     Alberto Madrigal                     brt.madrigal@gmail.com
     Guillaume Mahler                     guillaume.mahler@univ-lyon1.fr
-    Raphael Morales                      rmorales@iaa.es
+    Alireza Molaeinezhad                 amolaei@gmail.com
     Juan Molina Tobar                    juan.a.molina.t@gmail.com
     Francesco Montanari                  francesco.montanari@openmailbox.org
+    Raphael Morales                      rmorales@iaa.es
     Dmitrii Oparin                       doparin2@gmail.com
     Bertrand Pain                        bertrand.pain@inserm.fr
     William Pence                        william.pence@nasa.gov
diff --git a/doc/announce-acknowledge.txt b/doc/announce-acknowledge.txt
index 0e78c30..d3d1636 100644
--- a/doc/announce-acknowledge.txt
+++ b/doc/announce-acknowledge.txt
@@ -6,6 +6,7 @@ Andrés García-Serra Romero
 Bruno Haible
 Martin Kuemmel
 Javier Licandro
+Alireza Molaeinezhad
 Sebastian Luna Valero
 Samane Raji
 Alberto Madrigal
diff --git a/lib/wcs.c b/lib/wcs.c
index 06a8295..028e2ab 100644
--- a/lib/wcs.c
+++ b/lib/wcs.c
@@ -261,20 +261,45 @@ gal_wcs_read_fitsptr(fitsfile *fptr, size_t hstartwcs, 
size_t hendwcs,
         }
       else
         {
-          /* For a check.
+          /* For a check (we can't use 'wcsprt(wcs)' because this WCS isn't
+             yet initialized).
           printf("flag: %d\n", wcs->flag);
-          printf("naxis: %d\n", wcs->naxis);
-          printf("crpix: %f, %f\n", wcs->crpix[0], wcs->crpix[1]);
-          printf("pc: %f, %f, %f, %f\n", wcs->pc[0], wcs->pc[1], wcs->pc[2],
-                 wcs->pc[3]);
-          printf("cdelt: %f, %f\n", wcs->cdelt[0], wcs->cdelt[1]);
-          printf("crval: %f, %f\n", wcs->crval[0], wcs->crval[1]);
-          printf("cunit: %s, %s\n", wcs->cunit[0], wcs->cunit[1]);
-          printf("ctype: %s, %s\n", wcs->ctype[0], wcs->ctype[1]);
-          printf("lonpole: %f\n", wcs->lonpole);
-          printf("latpole: %f\n", wcs->latpole);
+          printf("NAXIS: %d\n", wcs->naxis);
+          printf("CRPIX: ");
+          for(i=0;i<wcs->naxis;++i)
+            { printf("%g, ", wcs->crpix[i]); } printf("\n");
+          printf("PC: ");
+          for(i=0;i<wcs->naxis*wcs->naxis;++i)
+            { printf("%g, ", wcs->pc[i]); } printf("\n");
+          printf("CDELT: ");
+          for(i=0;i<wcs->naxis;++i)
+            { printf("%g, ", wcs->cdelt[i]);} printf("\n");
+          printf("CD: ");
+          for(i=0;i<wcs->naxis*wcs->naxis;++i)
+            { printf("%g, ", wcs->cd[i]); } printf("\n");
+          printf("CRVAL: ");
+          for(i=0;i<wcs->naxis;++i)
+            { printf("%g, ", wcs->crval[i]); } printf("\n");
+          printf("CUNIT: ");
+          for(i=0;i<wcs->naxis;++i)
+            { printf("%s, ", wcs->cunit[i]); } printf("\n");
+          printf("CTYPE: ");
+          for(i=0;i<wcs->naxis;++i)
+            { printf("%s, ", wcs->ctype[i]); } printf("\n");
+          printf("LONPOLE: %f\n", wcs->lonpole);
+          printf("LATPOLE: %f\n", wcs->latpole);
           */
 
+          /* Some datasets may use 'angstroms' (not case-sensitive) in the
+             third dimension instead of the standard 'angstrom' (note the
+             differing 's'). In this case WCSLIB (atleast until version
+             7.3) will not recognize it. We will therefore manually remove
+             the 's' before feeding the WCS structure to WCSLIB. */
+          if( wcs->naxis==3
+              && strlen(wcs->cunit[2])==9
+              && !strncasecmp(wcs->cunit[2], "angstroms", 9) )
+            wcs->cunit[2][8]='\0';
+
           /* Fix non-standard WCS features. */
           if( wcsfix(fixctrl, fixnaxis, wcs, fixstatus) )
             {