+ } else {
+ average = sum / cnt;
+ sum = 0.0;
+ for (step = 0; step < steps; step++) {
+ if (finite(data[step * src->ds_cnt])) {
+ sum += pow((data[step * src->ds_cnt] - average), 2.0);
+ };
+ }
+ dst->vf.val = pow(sum / cnt, 0.5);
+ dst->vf.when = 0; /* no time component */