 
      CALL SEQUENCE...
       delhat  PSFIL DHFIL INPUT OUTPUT [ -plv VAL1 -def ]
 
 
      DESCRIPTION...
       delhat - COMPUTES THE FUNCION DELTA-HAT FOR ALL PRESSURE LEVELS
 
 
      AUTHOR  - J.D.Henderson, JUL 08/80.
      LAST REVISION: $Header: /data/armnraid1/cvs/RMNLIB/utils/rdiag/lspgm/delhat.ptn,v 4.7 2008/05/03 21:06:30 dugas Exp $
 
 
      PURPOSE - COMPUTES THE FUNCTION DELTA-HAT FOR A FILE OF SURFACE 
                PRESSURE GRIDS (ONE SET FOR EACH PRESSURE GRID)
 
      NOTES   - 1) PRESSURE VALUES ARE READ FROM STDIN
                2) DELTA-HAT IS 1.0 ABOVE THE SURFACE AND 0.0 BELOW IT
                3) THE MAXIMUM NUMBER OF LEVELS IS SET TO 999
 
 
      INPUT FILE...
       PSFIL = INPUT SERIES OF SURFACE PRESSURE GRIDS (MB).
 
      OUTPUT FILE...
       DHFIL = DELTA-HAT AT REQUESTED PRESSURE LEVELS FOR EACH
               PRESSURE GRID IN PSFIL.
 
 
      INPUT PARAMETERS...
 
       NLEV (plv) = NUMBER OF PRESSURE LEVELS (DEF=16, MAX=999).
                    IF NLEV IS NEGATIVE, EACH -NLEV LEVP VALUES ARE
                    READ WITH A I10 FORMAT OR AN E10.0 IF ITS VALUE
                    CONTAINS A DECIMAL POINT.
 
       LEV        = VALUES OF THE PRESSURE IN MILLIBARS AS CODED 
                    BY ROUTINE LVCODE. THE DEFAULTS ARE SPECIFIED
                    IN THE EXAMPLE BELOW.
 
       Notes: 1) The first input line is NOT read if any command-line
                 parameters are passed.
              2) Furthermore, the second line will not be read either
                 if the "-def" defaults processing mode is requested.
 
       READ( 5,5010 )  NLEV
       IF (NLEV.GT.0)
       READ( 5,5020 ) (LEV(I),I=1,NLEV)
       IF (NLEV.LT.0)
       READ( 5,5030 ) (LEV(I),I=1,-NLEV)
 5010  FORMAT(10X,I5)
 5020  FORMAT(16I5)
 5030  FORMAT(8E10.0)
 
 
      EXAMPLE OF INPUT CARDS...
 
    DELHAT   16
   10   20   30   50   70  100  150  200  250  300  400  500  700  850  925 1000
 
         01234567890123456789012345678901234567890123456789012345678901234567890
         1         2         3         4         5         6         7
 
 
      EXIT CONDITIONS...
        0 NO PROBLEMS
        1 TOO MANY OR NOT ENOUGH REQUIRED LEVELS
        2 PRESSURE LEVELS DO NOT VARY MONOTONICALLY
        3 PREMATURE EOF ON FILE PSFC
        4 ERROR READING FIRST LINE INPUT PARAMETERS
        5 ERROR READING SECOND LINE INPUT PARAMETERS
        6 LEV DOES NOT CONTAIN PRESSURE DATA
 
