Function: igp_test Purpose: Tests whether the idl/geopack module is installed Provides installation message if not installed Keywords: geopack_2008: set to use the 2008 version of the Geopack library. Must have version 9.2 of the IDL Geopack DLM installed to use the geopack_2008 keyword Returns: 1 on success 0 on failure Example: if(igp_test() eq 0) then return Notes: Should be called in all idl geopack wrapper routines $LastChangedBy: egrimes $ $LastChangedDate: 2014-11-04 10:10:32 -0800 (Tue, 04 Nov 2014) $ $LastChangedRevision: 16132 $ $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/external/IDL_GEOPACK/igp_test.pro $