*************************************************************************** User Notes for ICE Radio Data CD-ROM product. History C. Meetre May 1994 Draft A. Tekle June 1994 update OVERVIEW This ICE CD_ROM was produced using the Young Minds equipment attached to the SUN workstation LEPMFI. The data were transferred from 3480 cartridges on the IBM. The data were copied to the VAX and converted from IBM to VAX binary, compressed using the GZIP utility and transferred to the SUN workstation. The following types of data are included in this series of CD-ROMs: From To 1.5s modulated data (M) 1978 EOM 1.5s demodulated data (D) 1978 1987 108s averaged modulated data (A) 1978 EOM EDR data 1987 EOM DATA AVAILABILITY Demodulated data are available only during the period of the mission where higher bitrates were operational. Note that the original EDR data are only included for the low bitrate data. Data from 1978 to 1987 are recorded two months per disk. After this period, a single disk contains six months of data. There are two companion CD-ROM series for the high bit rate portion of the mission. One contains 30m averaged demodulated data and the other the 90s averaged demodulated data. Detailed information on the contents of the datasets may be obtained from the document 'ISEE-3 Radio Mapping Experiment Data Processing System' produced by CSC for NASA under contract NAS 5-24300 in 1980. BINARY FILES 1.5s modulated data, 1.5s demodulated data, and 108s averaged modulated data are supplied in binary files with a file for each day for each type of data. The naming convention is shown in the directory diagram below. The binary convention is VAX binary and uncompressed data can be read easily ONLY on a VAX. Attempts to read the data on other machines will necessarily require translation of the binary data. There are Sun FORTRAN routines to convert VAX data to SUN available in the SOFTWARE directory. The routines write out selected records to an ascii file and can be modified to write all records as SUN binary data. The original EDR data for the low bit rate period are supplied in IBM binary and are not compressed. COMPRESSION All ICE data, with the exception of the original EDR data files and plot files, are in compressed form. The GZIP utility was used for this and the disk contains the source, executables and build instructions for both the SUN and the VAX in the directory ZIP. SOFTWARE Simple FORTRAN routines for opening and reading uncompressed data files on the VAX and the SUN are supplied in the SOFTWARE directory. PLOT FILES A Postscript data presence plot is supplied in the PLOTS directory. Plots are not supplied for EDR data. The CD-Rom presence plots insert is for 1.5sec modulated data. DOCUMENTATION The following text files are supplied in the DOCUMENTS directory. REQUIREMENTS.TXT provides a detailed description of quality control and specifications used in the making of the ICE Radio data CD-Roms. GZIP.DOC is a description of the GZIP command and options provided with the GZIP utility software. ICE_108.TXT, ICE_15S.TXT and ICE_DEMOD.TXT list and describe the variables contained in the data files. QUALITY CONTROL Data were transferred from 3480 tape cartridge to IBM disk. In the event of data drops during the transfer from cartridge to disk, the copy program was rerun to fill in the data gap. If the data were not recovered after the second attempt, the procedure was repeated using the backup copy of the cartridge. No further attempts to recover the data were made if data were still missing after trying to copy from both cartridges. The text file MISSING.TXT in the DATA directory lists the intervals of unrecovered data. The files from the IBM disk were transferred to the VAX using FTP. The files were then converted from IBM to VAX binary and compressed using the GZIP utility on the VAX. The compressed files were transferred to the SUN workstation and an image created for copying to the CD. The integrity of the data was checked after each step, and compared for continuity (but not content) with the hardcopy one-day dynamic spectra. Content integrity was checked by direct comparison of selected records and by close graphic examination of selected days. A fuller description of the QC path is available from the REQUIREMENTS.TXT file in the DOCUMENTS directory. DIRECTORY STRUCTURE cdrom --|--- AAAREADME.TXT | |--- documents ---------- requirements.txt | gzip.doc | ice_108.txt | ice_15s.txt | ice_demod.txt | | |--- data ----------|---- 1_5s ----------- imyymmdd.gz | | | |---- 108 ----------- iayymmdd.gz | | | |---- demod ----------- idyymmdd.gz | | | |---- edr ----------- *.edr | | | |---- plots ----------- yymmdd.ps | | | |---- missing.txt | | |--- software --|--- sun ---|---- bin ----------- vax_to_sun | | | | | | | | |---- source ----------- *.F | | | | | | | |--- vax ---|---- exe ----------- *.exe | | | | | |---- source ----------- *.for | *.c | | |--- zip ----------|---- source ----------- GZIP source | & build files | |---- sun41x ----------- gzip | gunzip | |---- vms ----------- gzip.exe gunzip.exe For additional information contact: Dr. Robert G. Stone NASA/Goddard Space Flight Center Code 690 Greenbelt, MD. 20771 USA phone: 301-286-8631 alternate: 301-286-2608 Internet: stone@urap.gsfc.nasa.gov NSI: URAP::STONE