CALL SEQUENCE...
       betao  GPHIS GPHI BETA PS OUTPUT
 
 
      DESCRIPTION...
       betao  - COMPUTES BETA FOR OBSERVED HEIGHTS
 
 
      AUTHOR  - G.J.BOER, MAR 87.
      LAST REVISION: $Header: /home/cvs/RMNLIB/utils/rdiag/lspgm/betao.ptn,v 4.11 2014/09/25 20:20:45 dugas Exp $
 
 
 
      PURPOSE - COMPUTES THE FUNCTION "BETA" CORRESPONDING TO A SET
                OF GEOPOTENTIAL HEIGHTS ON PRESSURE LEVELS AND
                SURFACE GEOPOTENTIALS.
 
      NOTES   - 1) BETA MAY EXCEED 1 IN LOWEST LAYER.
                2) THE FORM OF BETA IS CONSISTENT WITH
                   THE USE OF PROGRAM VPINT
                3) MINIMUM NUMBER OF LEVELS IS 2, MAX IS 999.
 
 
      INPUT FILES...
       GPHIS  = INPUT GEOPOTENTIAL HEIGHTS OF SURFACE
       GPHI   = INPUT SETS OF GEOPOTENTIAL HEIGHTS
 
      OUTPUT FILES...
       BETA   = BETA GRID VALID AT EACH LEVELS
       PS     = OUTPUT SERIES OF INFERRED SURFACE PRESSURE
 
 
      EXIT CONDITIONS...
        0 NO PROBLEMS
        1 TOO MANY OR NOT ENOUGH  LEVELS
        2 FOUND SPECTRAL DATA ON GPHI
        3 FOUND "PR(NLEV) > 1013"
        4 UNABLE TO READ MONTAIN FILE
        5 UNABLE TO READ GEOPOTENTIAL FILE
        6 HIGHEST LEVEL BELOW TOP OF MONTAINS
        7 MORE THAN ONE SIZE IN INPUT DATA
        8 LAST GEOPOTENTIAL SET INCOMPLETE
        9 VERTICAL COORDINATE IS NOT PRESSURE
       10 FOUND WRONG VARIABLES
       11 VERTICAL LEVELS NOT MONOTONOUS