Telluride Preconditioning Routine

subroutine Precond (nunk, RHS, Solution, status)

  [snip]

  case (Jacobi)

     ! multistep weighted-Jacobi
     Solution%Values = zero
     do m = 1,JT%Control%steps
        call JACOBI (JT%Control%omega, Solution, RHS)
     end do

  case (SSOR)

     ! multistep weighted Gauss-Seidel
     Solution%Values = zero
     do m = 1,JT%Control%steps
        call SSOR (JT%Control%omega, Solution, RHS)
     end do

  case (Orth)

     ! orthogonal operator
     call JT_CG (..., RHS, ..., Solution%Values, ..., &
                 User_y_eq_Ax=Y_EQ_AX_ORTHOGONAL, &
                 User_Precond=PRECOND)

  [snip]