NAME

       PDL::GIS::Proj - PDL interface to the Proj4 projection library.

DESCRIPTION

       PDL interface to the Proj4 projection library.

       For more information on the proj library, see: http://www.remotesensing.org/proj/

AUTHOR

       Judd Taylor, Orbital Systems, Ltd.  judd dot t at orbitalsystems dot com

DATE

       18 March 2003

CHANGES

   1.32 (29 March 2006) Judd Taylor
           - Getting ready to merge this into the PDL CVS.

   1.31 (???) Judd Taylor
           - Can't remember what was in that version

   1.30 (16 September 2003) Judd Taylor
           - The get_proj_info() function actually works now.

   1.20 (24 April 2003) Judd Taylor
           - Added get_proj_info().

   1.10 (23 April 2003) Judd Taylor
           - Changed from using the proj_init() type API in projects.h to the
           - proj_init_plus() API in proj_api.h. The old one was not that stable...

   1.00 (18 March 2003) Judd Taylor
           - Initial version

COPYRIGHT NOTICE

       Copyright 2003 Judd Taylor, USF Institute for Marine Remote Sensing (judd@marine.usf.edu).

       GPL Now!

       This program 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.

SUBROUTINES

   fwd_transform($lon(pdl), $lat(pdl), $params)
       Proj4 forward transformation $params is a string of the projection transformation
       parameters.

       Returns two pdls for x and y values respectively. The units are dependant on Proj4
       behavior. They will be PDL->null if an error has occurred.

       BadDoc: Ignores bad elements of $lat and $lon, and sets the corresponding elements of $x
       and $y to BAD

   inv_transform($x(pdl), $y(pdl), $params)
       Proj4 inverse transformation $params is a string of the projection transformation
       parameters.

       Returns two pdls for lat and lon values respectively. The units are dependant on Proj4
       behavior. They will be PDL->null if an error has occurred.

       BadDoc: Ignores bad elements of $lat and $lon, and sets the corresponding elements of $x
       and $y to BAD

   get_proj_info($params_string)
       Returns a string with information about what parameters proj will actually use, this
       includes defaults, and +init=file stuff. It's the same as running 'proj -v'. It uses the
       proj command line, so it might not work with all shells. I've tested it with bash.