MODULE hlttst
#ifdef key_tam
   !!======================================================================
   !!                       ***  MODULE hlt_tst  ***
   !! NEMOTAM    : testing routine of linear-tangent hypothesis
   !!======================================================================
   !! History : 
   !! the direct:      !  10-07  (F. Vigilant)  Original code
   !!-----------------------------------------------------------------------
   !! * Module used
   USE in_out_manager  ! I/O manager
   USE par_tlm
   USE opahlt, ONLY: &
     & opa_hlt
   USE tanhlt, ONLY: &
     & tan_hlt
   USE hltinc

   IMPLICIT NONE

   !! * Routine accessibility
   PRIVATE

   PUBLIC &
      & hlt_tst 

CONTAINS

   SUBROUTINE hlt_tst
      !!-----------------------------------------------------------------------
      !!
      !!                  ***  ROUTINE hlt_tst  ***
      !!
      !! ** Purpose : Validate the linear-tangent hypothesis of the tangent with
      !!              with respect to the direct model
      !!
      !! ** Method  : Build or read a perturbation control vector dX and save
      !!              M(X, t=tO+p.T), M(X+dX, t=tO+p.T), LT(dX, t=tO+p.T)
      !!              t0=nit000
      !!              t = (nit000, nitend)
      !!              T: saving frequency
      !!
      !!              Post treatment need to be done to analyze the RMS of:
      !!              Y(t) = M(X, t=tO+p.T) - M(X+dX, t=tO+p.T) - LT(dX, t=tO+p.T)
      !!
      !!              Then, this routine is run three times
      !!
      !! ** Action  : Use 'nstg' swith as follows:
      !!                     0:  compute M(X, t=tO+p.T)
      !!                     1:  compute M(X+dX, t=tO+p.T)
      !!                     2:  compute LT(dX, t=tO+p.T)
      !!                     3:  compute and save dX only
      !!                   
      !! History : 
      !!        ! 10-07 (F. Vigilant) original code
      !!-----------------------------------------------------------------------
      !! * Modules used

      !! * Arguments
      !! * Local declarations

      SELECT CASE( nstg )
      CASE ( 0, 1, 3)
         CALL opa_hlt
      CASE ( 2 )
         CALL tan_hlt
      CASE DEFAULT
         CALL ctl_stop( '       Wrong value for hlt stage nstg. Must be 0, 1 or 2')
      END SELECT


   END SUBROUTINE hlt_tst

#endif
END MODULE hlttst