apply_preconditioner_sparse_crs_bicgstab Module Subroutine

    module subroutine apply_preconditioner_sparse_crs_bicgstab(self, b, x)
        implicit none
        class(type_solver_sparse_crs_bicgstab), intent(inout) :: self
        real(real64), intent(inout) :: b(:)
        real(real64), intent(inout) :: x(:)
        integer(int32) :: i, j

        select case (self%Preconditioner)
        case (0)
            !! No preconditioner
            return
        case (1)
            !! Jacobi preconditioner
            call apply_preconditioner_jacobi(self%N, self%M(:), b(:), x(:))
        case (2)
            !! ILU preconditioner
        end select

    end subroutine apply_preconditioner_sparse_crs_bicgstab