set_timer Subroutine

    subroutine set_timer(proc_timer, obj_level)
        != Start the timer for the specified object.
        != In:
        !=   obj_level (optional): timing level of the procedure.  Procedures with
        !=           a timing level above the iGlobalTimerLevel (specified in the
        !=           LOGGING block) are not timed.  The default timing level is 30.
        != In/Out:
        !=   proc_timer: The procedure timer.  Should contain the name of the
        !=           procedure and be SAVEd.  On exit, proc_timer%store points to the
        !=           appropriate entry in the timers array, which contains the
        !=           timing information for this object.  If the procedure is
        !=           called multiple times, the timer is not reinitialised, but
        !=           rather updated with new timing information (i.e. the current
        !=           timer is set).
        Use LoggingData, only: iGlobalTimerLevel
        type(timer) :: proc_timer
        integer, optional, intent(in) :: obj_level
        real(dp) :: t
        integer :: timer_level

        if (time_at_all) then

            if (.not. global_timing_on) then
                ! Initialise global timer.
                call init_timing()
            end if

            if (present(obj_level)) then
                timer_level = obj_level
            else
                timer_level = 30
            end if
            if (timer_level > iGlobalTimerLevel) then
                ! This object is too low-level to be timed.
                proc_timer%time = .false.
            else
                proc_timer%time = .true.
                if (.not. associated(proc_timer%store)) then
                    ! Have a new object.
                    itimer = itimer + 1
                    if (itimer > ntimer) then
                        call warning_neci('set_timer', 'ntimer parameter too small for the number of objects to be timed.')
                        proc_timer%time = .false.
                        timer_error = .true.
                        return
                    end if
                    proc_timer%store => timers(itimer)
                end if
                proc_timer%store%timer_name = proc_timer%timer_name
                proc_timer%store%ncalls = proc_timer%store%ncalls + 1
                if (.not. proc_timer%store%timing_on) then
                    ! Not in the middle of a recursive function.
                    ! A recursive function will have the recursive section between the
                    ! set_timer and halt_timer calls.  If we avoid refreshing the
                    ! start time for the timer of the recursive procedure, then the
                    ! correct timings are obtained.
                    ! Start the clock.
                    t = MPI_WTIME()
                    proc_timer%store%time_cpu = t
                    proc_timer%store%timing_on = .true.
                end if
            end if
        end if

    end subroutine set_timer