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Hi Waylon, re: > Based on your website at > www.unidata.ucar.edu/data/lightning.html?printer, I can contact you > regarding the use of Unidata software to analyze lightning data. I > already have software to extract lightning data from NLDN output > contained in netCDF files. However, I want to use another software > program to validate my initial results, in connection with a project. What is the original format of your NLDN data? The Unidata community of US universities receives their NLDN data as text bulletins in the Unidata Internet Data Distribution system. This data is then converted into a format that is usable by the display and analysis package that the user runs. > Could you provide a list of software programs that can be run on the > command-line in a Linux environment that will extract lightning data for > a particular horizontal area defined by latitude/longitude values? The two display and analysis packages we support that provide facilities for decoding of the IDD-delivered NLDN data are GEMPAK and McIDAS. We can give you access to GEMPAK, but not McIDAS since rur license with UW-SSEC limits us to making McIDAS available to educational institutions. > I > have latitude/longitude data that define the four corners of horizontal > boxes of size 20-km x 20-km. For each box, I want to be able to input > the latitude/longitude values into a command-line software program, > which will output lightning data that exist only within that box/area. If you are looking for a package that reads your netCDF files, then GEMPAK is not what you need. Instead, you could try using one of the netCDF analysis packages listed in the netCDF section of our website: Unidata HomePage http://www.unidata.ucar.edu netCDF HomePage http://www.unidata.ucar.edu/software/netcdf Software for manipulating or displaying netCDF data http://www.unidata.ucar.edu/software/netcdf/software.html If a "quick and dirty" look at your netCDF data would suffice, you could try using thehe 'ncdump' facility of netCDF. 'ncdump' can, among other things list out the values for variables contained in a netCDF. You could then use the dump output in conjunction with a Unix shell script to get the values of the variable(s) you want to compare to your other output. > The source files that I have are netCDF-formatted files that contain the > NLDN data. I think that one of the packages listed in the link above would be your best bet for analyzing your netCDF-formatted NLDN data. > Any help that you can provide would be greatly appreciated. I hope that this helped... > -- > ********************************************************************** > * Waylon G. Collins Voice: (361)289-0959 * > * NOAA/National Weather Service E-Mail: address@hidden * > * 300 Pinson Drive * > * Corpus Christi, TX 78406 * > * USA * > ********************************************************************** Cheers, Tom **************************************************************************** Unidata User Support UCAR Unidata Program (303) 497-8642 P.O. Box 3000 address@hidden Boulder, CO 80307 ---------------------------------------------------------------------------- Unidata HomePage http://www.unidata.ucar.edu **************************************************************************** Ticket Details =================== Ticket ID: IWD-747852 Department: Support netCDF Priority: Normal Status: Closed