Chimie Théorique » OpenPath

 subroutine hupdate_all(n, ds, dgrad, Hess)

  use Path_module, only :  hesupd,Hinv

  use Io_module, only : IoOut

  IMPLICIT NONE

  INTEGER, PARAMETER :: KINT=KIND(1)

  INTEGER, PARAMETER :: KREAL=KIND(1.0D0)

  INTEGER(KINT), INTENT(IN) :: n

  real(KREAL), INTENT(IN) :: ds(n), dgrad(n)

  REAL(KREAL),INTENT(INOUT) :: Hess(n:n)

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!

! This subroutine is a drive for the update of the Hessian 

! in the Quasi-Newton optimization step.

! We propose mostly update of the inverse Hessian.

!

! input:

!  - n: number of coordinates

!  - ds: GeomOld-Geom (expressed in the optimization coord.)

!  - dgrad: GradOld-Grad  (expressed in the optimization coord.)

!

!  input/output:

!  - Hess: old Hessian in input, replaced by updated Hessian on output

!

!!!!!!!!!!!!!!!!

!

! For now, we propose :

! - For update of inverser Hessian:

!      - BFGS

!

! - For update of hessian:

!      - Bofill (combination of Murtagh-Sargent and Powell-symmetric-Broyden

!      - Murtagh-Sargent

!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

  interface

     function valid(string) result (isValid)

       logical                  :: isValid

       character(*), intent(in) :: string

     end function valid

  end interface

  ! ======================================================================

  LOGICAL :: Debug

  ! ======================================================================

  debug = valid ('DEBUG HESS') .OR. Valid('DEBUG HUPDATE')

  if (debug) WRITE(*,*) "================================= Entering Hupdate_all ==============="

  SELECT CASE (Hinv)

     CASE (.TRUE.)

        SELECT CASE (HesUpd)

           CASE ("BFGS")

              Call Hinvup_BFGS(n,ds,dgrad,hess)

           CASE DEFAULT

              WRITE(*,*) Trim(HesUpd) // " not known: using BFGS"

              Call Hinvup_BFGS(n,ds,dgrad,hess)

         END SELECT

     CASE (.FALSE.)

        SELECT CASE (HesUpd)

           CASE ("BOFILL")

              Call Hupdate_Bofill(n,ds,dgrad,hess)

           CASE ("MS")

              Call Hupdate_MS(n,ds,dgrad,hess)

           CASE DEFAULT

              WRITE(*,*) Trim(HesUpd) // " not known: using Bofill"

              Call Hupdate_Bofill(n,ds,dgrad,hess)

           END SELECT

    END SELECT

end subroutine hupdate_all