{

    init {
        xx<-c();
        yy<-c();
        front <-c();
        gearsecs <-c();
    }

    #relevant {
    #    Data contains XDATA_UNITS("xdata", "GEARS");
    #}


    finalise {

        # fetch data
        front <- xdata("GEARS", "FRONT");
        rear <- xdata("GEARS", "REAR");
        gearsecs <- xdata("GEARS", secs);

        #duration  1 5 6 8
        #durationtmp 0 1 5 6 8
        # secs to duration
        durationtmp <- gearsecs;
        append(durationtmp,0,0); # add 0 to shift indexes
        remove(durationtmp, length(durationtmp) -1, 1); # remove last to have same length

        duration <- gearsecs - durationtmp;

        # remove abnormal values (ex: 255 or 0)
        first <- head(duration,1);
        duration <- sapply(gearsecs,front[i]<200 ? x : 0 )[x<>0];
        #duration <- sapply(duration,front[i]<200 ? x : 0 );
        #annotate(label,"max:",max(duration));
        if(gearsecs[0]=255){
            append(duration,first,0);
        }
        rear <- sapply(rear,front[i]<200 ? x : 0 )[x<>0];
        front <- sapply(front,front[i]<200 ? x : 0 )[x<>0];

        annotate(label,"Front:",min(front));

        # sort
        multisort(ascend, rear, duration);

        # keep only rear when front is min
        rear <- sapply(rear,front[i]=min(front) ? x : 0 )[x<>0];
        duration <- sapply(duration,front[i]=min(front) ? x : 0 )[x<>0];

        yy <- aggregate(duration, rear, sum);
        #annotate(label,"yy:",yy);
        xx <- uniq(rear);

        multisort(descend,yy,xx);
    }

    x { xx; }
    y { yy/3600; }

}