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* These programs were developed in and are available from ATD, RAP, or ASP and are included here for completeness.
Webmaster: L. Jay Miller at ljmill@ucar.edu
This document briefly describes several data analysis software packages that are maintained by NCAR/MMM, are in the public domain, and are made available for non-commercial use. Source code tarfiles are available along with documentation (usually postscript files), examples, and other relevant files. All MMM-developed source code is free, but copyrighted and UCAR is the copyright holder. In most subdirectories there are postscript files (copyright.ps) containing the copyright statement. These software packages use utilities that are within the NCAR Graphics package. You must obtain that package from NCAR/SCD if you do not already have it installed. The NCAR/SCD GBYTES-SBYTES--> software package is used for handling binary packing of data.
PPI-MMM is a program to analyze radar measurements taken at spherical coordinates (range, azimuth, and elevation). It accepts radar data in any of the following formats: field formats (FF) from the NCAR/ATD radar processors (RP-3 through 7), universal format (UF), the DORADE (airborne and ground-based radars, including ATD/SOLO sweep files), and the National Climate Data Center (NCDC) NEXRAD Level II format. Data are processed by sweeps from PPI (surveillance or azimuth sector at a constant elevation angle) or RHI (changing elevation angle at a constant azimuth angle) scans. Several options are available for manipulating the data algebraically and displaying it.
SPRINT is a program to interpolate radar measurements taken at spherical coordinates (range, azimuth, and elevation) to regularly-spaced Cartesian or longitude-latitude grids, in either constant height or constant elevation angle surfaces. It accepts radar data in any of the ATD field, univeral, DORADE, or NEXRAD Level II formats. SPRINT outputs interpolated data in pure binary format readable by CEDRIC. A description of the CEDRIC binary format can be found in Appendix D of the documentation for SPRINT or CEDRIC. Data from PPI scans can be interpolated to Cartesian or longitude-latitude grids, either at constant height or constant elevation angle surfaces. Both airborne helical scans and constant-azimuth (RHI) scans from ground-based radars are only interpolated to Cartesian grids (X, Y, and Z).
CEDRIC is a mesoscale data analysis program that processes datasets on regular Cartesian and longitude-latitude grids. The analysis options include many numerical operations such as algebraic, filtering, and Doppler radar wind synthesis, both ground-based and airborne, as well as graphical operations. Several REMAPpings (interpolations) are possible: XYE --> XYZ, LLE--> LLZ, XYE <--> LLE, and XYZ <--> LLZ, where XY (LL) is a regular Cartesian (longitude-latitude) grid. Z (E) refers to a constant height (elevation angle) surface. CEDRIC uses its own self-describing, binary format as well as the network Common Data Format (netCDF) that was developed by NASA and UCAR's UNIDATA.
Since the CEDRIC pure binary format is portable, very fast, and compact, it is recommended for general use. However netCDF is an alternative format which is highly portable, and there are existing software packages that can directly read this format. Thus, if you want to use CEDRIC files in other software packages, it might be easier to create them in this format. The pure binary format can also be used in your own programs, but it would be harder to do. Input and output to netCDF files is slower and the files are bigger, so it is not recommended for general, everyday use on the same platform type. Furthermore, only one volume can be written to netCDF files. With the pure format, up to 25 volumes can be placed in a single file. Writing out to a file that already exists with the netCDF format option selected will cause the contents of the existing file to be overwritten. Since no appending takes place with netCDF, users should exercise caution to avoid accidentally overwriting existing datasets.
CEDIO is a module consisting of input/output routines for the CEDRIC pure binary format. These routines are useful for interfacing CEDRIC-generated gridded data with other software packages.
Users must also obtain and install these software packages:
These data analysis software packages were developed and are maintained by NCAR/MMM and are released subject to any and all obligations on the user as specified in the copyright statement. It should be understood by the recipient/user that NCAR/MMM assumes no liability for any errors contained in the code. It is expected that appropriate credit be given to software author(s) and to the National Center for Atmospheric Research in any publications that result from the use of any of these software packages or in any software package that includes any of these software packages, in part or in whole.
All CEDRIC, SPRINT and PPI_MMM software packages are available from the MMM
web site at "http://box.mmm.ucar.edu/radarcode/.
Please note: These codes have been frozen and have not been updated since the retirement of
Jay Miller in 2004.
If you have problems down loading the code please contact sherrie@ucar.edu
These software packages make use of the
NCAR Graphics package
available from NCAR's Scientific Computing Division and the
network Common
Data Format (netCDF) software available from UCAR's UNIDATA.
Copyright © UCAR 1997 - Disclaimer - mmminfo@ncar.ucar.edu
Last Modified: 22 Jan 1999