public double MacroRecall() {
                if (computed == 0) countStuff();
                double mrec = 0;
                for (int i=0; i<catnum; i++) {
                        if ((tp[i] != 0) && (tp[i]+fn[i] != 0))
                                mrec += tp[i]/(tp[i]+fn[i]);
                }
                return mrec/catnum;
        }