}
for (int position = 0; position < groupIdsBlock.getPositionCount(); position++) {
checkState(values.advanceNextPosition());
checkState(masks == null || masks.advanceNextPosition());
checkState(sampleWeights == null || sampleWeights.advanceNextPosition());
long sampleWeight = computeSampleWeight(masks, sampleWeights);
if (!values.isNull() && sampleWeight > 0) {
long groupId = groupIdsBlock.getGroupId(position);
double inputValue;