[fitsbits] WCSLIB 2.5

[Mark Calabretta]

WCSLIB 2.5 is now available.  

WCSLIB 2.5 is an intermediate release.  It goes as far as possible in
fixing a few minor problems and adding some small enhancements which have
accumulated in the three years since version 2.4 was released (change
logs appended).

However, WCSLIB 2.5 does not fully implement the latest draft of
"Representations of Celestial Coordinates in FITS" by Calabretta and
Greisen (c.f. http://www.atnf.csiro.au/~mcalabre) since that would
require changing the API and I am reluctant to do that until final
agreement on the FITS WCS proposal is obtained.

Also, for the first time, this release includes PGCRVL, a PGPLOT routine
(FORTRAN) which draws and labels curvilinear coordinate grids.  It was
designed and written with WCSLIB in mind but can handle other types of
non-linear/curvilinear coordinate grids.  Example PGCRVL grids can be
seen at

   http://www.atnf.csiro.au/~mcalabre/pgcrvl.html

WCSLIB 2.5 may be collected from

   Australia:     ftp://ftp.atnf.csiro.au/pub/software/wcslib/
   USA (mirror):  ftp://fits.cv.nrao.edu/fits/src/wcs/


Looking into the crystal ball: once the FITS WCS proposal is accepted by
the IAU I envisage that the next release of WCSLIB (3.0) will implement

   1) The change from CDELT+PC matrix to CD matrix.

   2) Enhanced range of projection parameters, from the present 10 (total)
      to 100 on each axis (i.e. 200) to handle astrometric plate solutions
      in the TAN projection.

The first of these will require a change to the interfaces of the C and 
FORTRAN libraries, the second will only affect the FORTRAN library.


Mark Calabretta
Australia Telescope National Facility


>>>>> C library >>>>>

WCSLIB version 2.5 (1999/12/14)
-------------------------------

* Added copyright notice to header files and prefixed include guard names with
  "WCSLIB_".

* Fixed cube face handling in wcsfwd() and wcsrev(), reported by Doug Mink
  (dmink at cfa.harvard.edu).  Allow more general face layout in the inverse
  quadcube projections.

* Fixed the problem in wcsmix() where it failed to find a valid solution when
  the solution point lay at a native pole of a projection in which the pole is
  represented as a finite interval.  However, wcsmix() will only ever return
  one solution even when two or more valid solutions may exist.

* wcsmix() now accepts viter in the range 5 - 10, the specified value will be
  pushed up or down into this range if necessary.

* The projection routines for AZP, TAN, SIN, ZPN, and COP now return error 2
  if (phi,theta) correspond to the overlapped (far) side of the projection.
  This strict bounds checking can be switched off by setting prj->flag to -1
  (rather than 0) when the projections are initialized.

* The upper level routines, wcsset(), wcsfwd(), wcsrev(), and wcsmix(), now
  recognize the NCP projection and convert it to the equivalent SIN
  projection.  The lower level routines do not recognize NCP.

* Extracted definitions of mathematical constants (PI etc.) from proj.h into
  wcsmath.h in order to avoid conflicts with their definition in math.h in
  some systems (such as Linux).
 
* Describe the two alternate representations of the quadcube projections
  (i.e. faces laid out or stacked) in the prologue of wcs.c.


>>>>> FORTRAN library >>>>>

WCSLIB version 2.5 (1999/12/14)
-------------------------------

* Fixed cube face handling in WCSFWD and WCSREV, reported by Doug Mink
  (dmink at cfa.harvard.edu).  Allow more general face layout in the inverse
  quadcube projections.
 
* Fixed the problem in WCSMIX where it failed to find a valid solution when
  the solution point lay at a native pole of a projection in which the pole is
  represented as a finite interval.  However, WCSMIX will only ever return one
  solution even when two or more valid solutions may exist.

* WCSMIX now accepts VITER in the range 5 - 10, the specified value will be
  pushed up or down into this range if necessary.

* The projection routines for AZP, TAN, SIN, ZPN, and COP now return error 2
  if (phi,theta) correspond to the overlapped (far) side of the projection.
  This strict bounds checking can be switched off by setting PRJ(11) to -1
  (rather than 0) when the projections are initialized.

* The upper level routines, WCSSET, WCSFWD, WCSREV, and WCSMIX, now recognize
  the NCP projection and convert it to the equivalent SIN projection.  The
  lower level routines do not recognize NCP.
 
* Describe the two alternate representations of the quadcube projections
  (i.e. faces laid out or stacked) in the prologue of wcs.f.