GDMOD moves grids from one GEMPAK grid file to another.


INPUT PARAMETERS
 
    GDFILE    *Grid file
    GDOUTF    *Output grid file
    GDNUM     *Grid numbers
    GPACK     *Packing type/number of bits
 
 
PROGRAM DESCRIPTION
 
    GDMOD moves grids from an input grid file to an output
    file.  The input grid file name is specified in GDFILE.  The
    output grid file name is specified in GDOUTF.  The input and
    output grid files must have the same navigation information.

    The numbers of the grids to be moved are specified in GDNUM.
    Either a list of grid numbers, with semicolons separating the
    numbers, or a range of grid numbers, with the first and last
    numbers separated by a dash, may be entered.

    The output grids will be packed using the information in
    GPACK.

 
EXAMPLES
 
    1.  Add grids 1, 4 and 7 from file, OLD.GRD, to file NEW.GRD.
        Pack the data using 16 bits for each data value.

        GDFILE  =  old.grd
        GDOUTF  =  new.grd
        GDNUM   =  1;4;7
        GPACK   =  16/grib


    2.  Copy all the grids in TODAY.GRD to DEC.GRD.  Do not
        pack any data.

        GDFILE  =  today.grd
        GDOUTF  =  dec.grd
        GDNUM   =  all
        GPACK   =


ERROR MESSAGES
 
    [GDMOD  -1]     Fatal error initializing TAE.
    [GDMOD  -2]     Fatal error reading TAE parameters.
    [GDMOD  -3]     Invalid grid range entered.
    [GDMOD  -4]     Grid number ... is invalid.
    [GDMOD  -5]     There are no grids in file ....
    [GDMOD  -6]     No valid grids in list.
    [GDMOD  -7]     Error reading input grid.
    [GDMOD  -8]     Error writing output grid.
    [GDMOD  -9]     Error opening files.
    [GDMOD -10]     Files contain different navigations.
    [GDMOD -11]     Too many grids to transfer.