CALL SEQUENCE...
       ggaps  GG PS INPUT OUTPUT [-lx VAL1 -i VAL3 -d60  VAL5 -nhem VAL7
                                  -ly VAL2 -j VAL4 -dgrw VAL6 -kind VAL8] 
 
 
      DESCRIPTION...
       ggaps   - CONVERT LAT-LONG FILE TO POLAR STEREOGRAPHIC GRID FILE 
 
 
      AUTHOR  - J.D.Henderson,  DEC 01/80.
      LAST REVISION: $Header: Code-beta-01-de-r.diag_6.3.1-et-cdf2rpn_2.2.1 @ Tue, 15 Nov 2016 12:28:00 -0500 (Bernard Dugas) $
 
 
      PURPOSE - CONVERTS A FILE OF LAT-LONG GRIDS TO A FILE
                OF HEMISPHERIC POLAR STEREOGRAPHIC GRIDS. 
                INTERPOLATION IS EITHER LINEAR OR CUBIC. 
 
      NOTES: 1) THE INPUT GRID TYPE IS ALWAYS ASSUMED TO BE GAUSSIAN
                WHEN DEALING WITH CCCma FILES.
             2) FOR RPN/CMC STANDARD FILES, ALL OF THE KNOWN INPUT
                GRID TYPES ARE SUPPORTED, EXCEPT THE '#' TYPE.
             3) DIGITAL FILTERING WILL BE APPLIED BEFORE INTERPOLATION
                IF THE DESTINATION GRID IS AT MUCH LOWER RESOLUTION THAN
                THE INPUT. A MESSAGE WILL BE PRINTED WHEN THIS IS DONE.
 
 
      INPUT FILE... 
       GG = LAT-LONG GRIDS. HEMISPHERIC POLAR STEREOGRAPHIC
            GRIDS ARE ALSO SUPPORTED IN CMC/RPN FILES.
 
      OUTPUT FILE... 
       PS = HEMISPHERIC POLAR STEREOGRAPHIC GRIDS 
 
 
      INPUT PARAMETERS... 
 
       LX,LY = POLAR-STEREOGRAPHIC GRID DIMENSIONS. IF LX=0, THE FIRST
               SIX VALUES ON THE CARD WILL ASSUME THEIR DEFAULT VALUES
               WHICH WILL PRODUCE A CCC FILE ON THE STANDARD CMC GRID. 
       PI,PJ = (I,J) GRID COORDINATES OF THE POLE (DEFAULT IS (26.,28.)
       D60   = GRID LENGTH AT 60 DEGREES (METERS) 
              (DEFAULT VALUE 3.81E5 = 381 KM).
       DGRW  = ORIENTATION IN THE GRID WITH RESPECT TO THE GREENWICH
               MERIDIAN (DEG) (DEFAULT 350.).
       NHEM  = 1 or N, FOR N. HEM. (DEFAULT FOR GLOBAL GG)
               2 or S, FOR S. HEM. 
       KIND  = INTERPOLATION TYPE:
               1 = LINEAR,
               2 = NEAREST NEIGHBOR (only RPN/CMC Standard files),
               OTHERWISE CUBIC.
 
       NOTE THAT IF GG CONTAINS HEMISPHERIC DATA, THE DEFAULT NHEM
       VALUE IS THEN THAT OF THE FIRST GRID IN GG
 
       READ( 5,5010 ) LX,LY,PI,PJ,D60,DGRW,NHEM,KIND 
 5010  FORMAT(10X,2I5,2E5.0,2E10.0,2I5) 
 
 
      EXAMPLE OF CARD READ... 
 
     GGAPS   51   55   26   28    3.81E5      -10.    1    1 
 
         0123456789012345678901234567890123456789012345678901234567890
         1         2         3         4         5         6         7
 
 
      EXIT CONDITIONS...
        0 NO PROBLEMS
        1 PREMATURE EOF ON GG
        2 UNSUPPORTED INPUT DATA TYPE
        3 MISMATCH BETWEEN NHEM AND IBUF(7)
        4 ERROR ABORT READING INPUT