***** File SOFTINFO.TXT                                                       
                                                                              
     This information file is located in the SOFTWARE directory, which        
contains source and executable code which should be of use to the IHW Archive 
user.  For HAL_0023, the SOFTWARE directory has been divided into seven       
subdirectories: BROWSE, COMPRESS, DECOMP, OBSNTERP, IMDISP, FTB, and UTILS.   
Each of these subdirectories has all of the necessary information to compile  
and/or run the programs located in that subdirectory.                         
                                                                              
     The BROWSE subdirectory contains the IBM FORTRAN code used to make the   
LSPN BROWSE images.  The COMPRESS subdirectory contains the IBM FORTRAN code  
for a previous pixel compression algorithm that was used to compress the LPSN 
digitized images.  The compressed images can be found on HAL_0001 through     
HAL_0018.  The DECOMP subdirectory contains the C-code routines that can be   
used to uncompress the LSPN compressed images.  The code is designed to run on
an IBM PC or clone.                                                           
                                                                              
     The OBSNTERP subdirectory contains software to interpolate the P/Halley  
ephemeris file EPHEM.TAB (in the EPHEM directory).  The source code is        
OBSNTERP.FOR (see the NOTE below), executable modules of which are called     
PCNTERP.EXE and VAXNTERP.EXE (for use in MS-DOS and VAX/VMS environments,     
respectively).  The IMDISP subdirectory contains software to display the image
and spectral data contained on the IHW CD-ROMs; this software, provided by    
PDS/JPL and improved by outside users, works only in the PC MS-DOS            
environment.  The FTB subdirectory contains software to browse FITS Tables;   
this software, provided by the Astronomical Data Center (ADC) of the National 
Space Science Data Center (NSSDC, at NASA/GSFC), runs only in the VAX/VMS     
environment.  The UTILS subdirectory contains software to concatenate separate
FITS headers and datafiles into true FITS byte streams; the software also     
works in reverse. This code, which runs only in the PC MS-DOS environment, was
provided by the IHW Large-Scale Phenomena Discipline at NASA/Goddard Space    
Flight Center.                                                                
                                                                              
                                                                              
*************  NOTE  **************                                           
                                                                              
The executable version of OBSNTERP that was placed on the Large-Scale         
Phenomena compressed image discs (Volumes 1-18) contains a small bug, and     
Archive users should not use it.  The OBSNTERP.FOR source and executable codes
placed on these discs (Volumes 19-23) have had this bug corrected.  We regret 
any inconvenience this may cause.