PDSVAL

     PDSVAL provides a way to enter explicitly PDS numbers identifying
     a grid by parameter, level, vertical coordinate type, and time.
     None, some, or all of them may be entered.  Default values are
     determined from the GEMPAK grid label information and the GEMPAK
     grid GRIB lookup tables.

     The input has the following form:

     parameter # %vertical coordinate type # @level # ^time

     or

     parm name %vertical coordinate name @level # ^time

     The parameter number or name, if given, must appear first.  It
     is not preceded by any marking delimiter.  The parameter number
     will be assigned to PDS byte 9.  After the parameter number, the
     entries may be given in any order.  The parameter may be entered
     as a name to be found and matched to a number using the GEMPAK
     grid GRIB lookup tables.

     The vertical coordinate type number is preceded by % as a marking
     delimiter.  The number entered will be assigned to byte 10.  The
     vertical coordinate may be entered as a name to be found and
     matched to a number using the GEMPAK grid GRIB lookup tables.

     The level information is preceded by @.  A single level value
     or two level values separated by a colon may be entered following
     the @ symbol.  This information is assigned to bytes 11 and 12.

     The time information is entered following the ^ symbol in the form
     YYYYMMDD/HHMMFhhhmm.  This is a standard GEMPAK time, except that
     the year must have four digits.  This information is assigned to
     bytes 13 through 25, with forecast time units assumed to be hours.
     Any accumulation period must come from information imbedded within
     the GEMPAK parameter name.