PAL Library

The Starlink Positional Astronomy Library (PAL) is a C implementation of the
SLALIB API. It is distributed under the GPL and uses the SOFA library wherever
possible.

V0.9.7

- Enable light deflection in palAmpqk.

V0.9.5

- Add light deflection to palAmpqk. SLALIB always had it but for some reason
  the relevant piece of code never got ported to PAL.

V0.9.4

- Add light deflection to palMapqkz (thanks to Scott Daniel)
- Add test for palMapqk (thanks to Scott Daniel)
- Correctly disable documentation build when running outside of a Starlink
  environment.

V0.9.3

- Fix value of small in palFk524. Typo in port from Fortran
  had removed the "e" in the number. Thanks to @danielsf.

- Add test for palFk524

V0.9.2

Thanks to Github user @nega0 for some BSD build fixes.

More STARCONF_DEFAULT_PREFIX fixes for Scons file and for
document building.

New configure option: --with-erfa to allow the ERFA
root location to be specified.

V0.9.1

Now checks for STARCONF_DEFAULT_PREFIX environment variable
when deciding whether a Starlink environment is present. This
was more reliable than checking for STARLINK_DIR.

V0.9.0

Add palPcd and palUnpcd

V0.8.0

Add palEcleq

V0.7.0

Add palPolmo.

V0.6.0

New function, palVers, provides API access to the PAL
version number as a string or integer.

V0.5.1

The configure script was getting confused if run outside of
Starlink without using --without-starlink. This was because
$STARLINK is set in the script if it is not set and the
configure script was assuming $STARLINK would be unset
outside of a Starlink environment. The configure script
now keys off $STARLINK_DIR but that may interact badly
if STARLINK_DIR is set and --without-starlink is used.

An experimental SConstruct build script is now available
for users of scons.

SUN/267 has been synced up with the associated source files.

palIntin now respects the isblank configure check (as it
should have done all along).

Minor clean ups of some source prologues.

V0.5.0

Now works with ERFA <https://github.com/liberfa/erfa>.
The configure script has been modified to first check
for ERFA and then check for SOFA.

V0.4.0

New routines ported from SLA: palRefv, palAtmdsp
New routine inherited from SOFA: palRefcoq

Minimum SOFA version now 2013-12-02

palObs: Now includes telescope positions for APEX and NANTEN2

The autotools build scripts now require autoconf version 2.69.

Thanks to Github user @nega0 for some BSD build fixes.

A subset of the routines have been relicensed using LGPL
to allow them to be included in the AST library. Thanks to
Patrick Wallace for giving this permission.

A paper on PAL has been published at ADASS:
  http://adsabs.harvard.edu/abs/2013ASPC..475..307J

V0.3.0

Add refraction code and support palOap and palAop. For closer compatibility
with SLA for testing purposes the refraction routines internally use
clones of slaNutc, slaEqeqx, slaGmst and slaGeoc. Once the code has
been verified further the PAL/SOFA routines will be used instead. Switching
routines seems to change the results in palTest by about 0.05 arcsec.

V0.2.0

Improve configure script when not in a Starlink build environment. Use

  ./configure --prefix=/path/to/install

when Starlink is not available and add --without-starlink if Starlink
is present but should not be used.

V0.1.5

Explcitly look for libm rather than relying on SOFA to pull it in.

V0.1.4

Check for isblank() function and fall back if it is missing.

V0.1.3

Improve copysign() detection.

V0.1.2

Check for copysign() c99 function and fall back if it is missing.

V0.1.1

The palDrange function has been modified so that it now returns +PI if
the supplied angle is +PI (previously, it returned -PI in these cases).


V0.1.0

Initial release with sufficient SLALIB API for AST and the Astro::Coords perl module.
