The IDL Geopack DLM is a Dynamic Link Module (DLM) for the Interactive Data Language (IDL) by Research Systems, Inc. The purpose of this library is to provide easy access to the GEOPACK Fortran library by N. A. Tsyganenko and related routines. I do not claim any rights to those routines. My only intellectual assets are in the interface itself. The interface allows calling of the Geopack functions, which are commonly used in space physics, from the IDL command line without any knowledge of Fortran or C. All commands behave like native IDL procedures.

Please report bugs to the author (haje.korth@jhuapl.edu).

NEW (05/21/2009): Another handy DLM for converting between geographic and altitude-adjusted corrected geomagnetic (AACGM) coordinates is available here. These routines were recently updated and include the Year 2005 spherical harmonic coefficients.

IDL Geopack DLM for Windows (32 bit):
IDL GEOPACK DLM v6.7 for Windows

IDL Geopack DLM for Linux (32 & 64 bit):
IDL GEOPACK DLM v6.7 for Linux

IDL Geopack DLM for Mac OS X (32 bit PPC, 32 & 64 bit Intel):
IDL GEOPACK DLM v6.7 for Mac OS X

IDL Geopack DLM for SunOS (32 & 64 bit):
IDL GEOPACK DLM v6.7 for SunOS

Version History:
v1.0: Initial release.
v2.0: Implemented Geopack 2005 library.
v2.1: License check removed.
v2.2: T04S model implemented.
v2.3: Removed obsolete Fortran exports in DLL (Windows only).
v2.4: Fortran code recompiled with IVF 9.0 (so far Windows only).
v2.5: Minor fixes.
v2.6: Added routine GEOPACK_HELP and HELP keyword to all routines.
v2.7: Vectorized GEOPACK_TRACE.
v3.0: Project moved to VS2005 and IVF 9.1.
v3.1: Fixed compile warnings.
v3.2: Fixed conversion of input parameters when DEGREE keyword is set.
v3.3: Fixed serious bugs with interface to T96 and T04S models. Created post v4.1.
v4.0: Project moved to IDL 6.3.
v4.1: Fixed serious bugs with interface to T96 and T04S models.
v4.2: Updated help messages and documentation.
v4.3: Recompiled with IVF 9.1 release version and linked against idl.lib from IDL 6.3 release version to ensure compatibility.
v4.4: Geopack May 2006 updates and T01 & TS04 June 2006 updates incorporated. Warning issued when using storm-time T01 model since it is no longer maintained.
v4.5: Changed processing of HELP keyword to show info without invoking GEOPACK_RECALC first.
v4.6: Output array dimensions now identical with input array dimensions.
v4.7: Added NOBOUNDARY keyword to GEOPACK_TRACE for overriding the boundary limits built into the original routine.
v4.8: Added DATE keyword to GEOPACK_RECALC.
v4.9: Increased the maximum number of trace steps in GEOPACK_TRACE from 1000 (Geopack default) to 10000.
v5.0: Minor internal changes to definition of field line elements arrays in GEOPACK_TRACE.
v5.1: Added GEOPACK_GETW for calculation of W parameters used in T04S model.
v5.2: Combined GEOPACK_T01N and GEOPACK_T01S in GEOPACK_T01; the storm-time version of T01 is now invoked using the STORM keyword (remember, the T01_S is now obsolete). Added QUIET keyword to GEOPACK_T01 and GEOPACK_TRACE to suppress "T01_S obsolete" warning. Renamed GEOPACK_T04S to GEOPACK_TS04. Added GEOPACK_GETG routine to calculate G parameters used in T01 and T01_S models.
v5.3: Minor fixes to eliminate compiler warnings under Linux.
v5.4: FLINE keyword in GEOPACK_TRACE returns actual field line points only and is no longer zero-padded.
v5.6: Fixed bug in leap year logic.
v5.7: Output values are returned as scalars if input values are scalars.
v5.8: Removed references to YEAR keyword in routines GEOPACK_DIP and GEOPACK_TRACE from help text and documentation.
v5.9: Added keywords IOPGEN, IOPT, IOPB, and IOPR to routines GEOPACK_TS04 and GEOPACK_TRACE to improve control of TS04 model.
v6.0: Added range check for keywords IOPGEN, IOPT, IOPB, and IOPR.
v6.1: Minor changes to allow compilation on SunOS and Mac OS X (Intel).
v6.2: Fixed bug in GEO to GSE coordinate transformation.
v6.3: Added trace routine with refined foot point location by Vassilis Angelopoulos. Access to routines is provided with keyword REFINE to GEOPACK_TRACE. Tracing to ionosphere or equatorial plane is controlled with keywords IONOSPHERE and EQUATOR, respectively. Other minor fixes and improvements.
v6.4: Added EPOCH keyword to applicable routines to allow internal execution of RECALC during vectorized processing. Added GEOPACK_EPOCH for converting between UTC and EPOCH time formats.
v6.5: Minor bug fixes in GEOPACK_EPOCH.
v6.6: Bug fixes related to EPOCH keyword. Added foot point to field line array in GEOPACK_TRACE.
v6.7: Bug fix for tracing to the equatorial plane with GEOPACK_TRACE /REFINE.