GETGB1

The GETGB1 routine reads and unpacks a grib message.  The routine
           reads an associated grib index file (unless it already was read).
           and finds in the index file a reference to the grib message requested.
           the grib message request specifies the number of messages to skip
           and the unpacked pds and gds parameters.  (a requested parameter
           of -1 means to allow any value of this parameter to be found.)
           If the requested grib message is found, then it is read from the
           grib file and unpacked.  Its message number is returned along with
           the unpacked pds and gds parameters, the unpacked bitmap (if any),
           and the unpacked data.  If the grib message is not found, then the
           return code will be nonzero.

USAGE:    CALL GETGB1(LUGB,LUGI,JF,J,JPDS,JGDS,
                      GRIB,KF,K,KPDS,KGDS,LB,F,IRET)

   Input arguments:
      LUGB         LOGICAL UNIT OF THE UNBLOCKED GRIB DATA FILE
      LUGI         LOGICAL UNIT OF THE UNBLOCKED GRIB INDEX FILE
      JF           INTEGER MAXIMUM NUMBER OF DATA POINTS TO UNPACK
      J            INTEGER NUMBER OF MESSAGES TO SKIP
                   (=0 TO SEARCH FROM BEGINNING)
                   (<0 TO REOPEN INDEX FILE AND SEARCH FROM BEGINNING)
      JPDS         INTEGER (25) PDS PARAMETERS FOR WHICH TO SEARCH
                   (=-1 FOR WILDCARD)
                   LOOK IN DOC BLOCK OF W3FI63 FOR ARRAY KPDS
                   FOR LIST OF ORDER OF UNPACKED PDS VALUES. IN
                   MOST CASES YOU ONLY NEED TO SET 4 OR 5 VALUES
                   TO PICK UP RECORD.
      JGDS         INTEGER (22) GDS PARAMETERS FOR WHICH TO SEARCH
                   (ONLY SEARCHED IF JPDS(3)=255)
                   (=-1 FOR WILDCARD)

   Output arguments:
      GRIB         GRIB DATA ARRAY BEFORE IT IS UNPACKED
      KF           INTEGER NUMBER OF DATA POINTS UNPACKED
      K            INTEGER MESSAGE NUMBER UNPACKED
                   (CAN BE SAME AS J IN CALLING PROGRAM
                   IN ORDER TO FACILITATE MULTIPLE SEARCHES)
      KPDS         INTEGER (25) UNPACKED PDS PARAMETERS
      KGDS         INTEGER (22) UNPACKED GDS PARAMETERS
      LB           LOGICAL (KF) UNPACKED BITMAP IF PRESENT
      F            REAL (KF) UNPACKED DATA
      IRET         INTEGER RETURN CODE
                     0      ALL OK
                     96     ERROR READING INDEX FILE
                     97     ERROR READING GRIB FILE
                     98     NUMBER OF DATA POINTS GREATER THAN JF
                     99     REQUEST NOT FOUND
                     OTHER  W3FI63 GRIB UNPACKER RETURN CODE

 


  
W3lib.tar
  
Library contains Fortran 90 decoder/encoder
   routines for GRIB edition 1. (Fortran90) 

   Date posted: 2/22/2007