HDateTime ts = range.start;
boolean isBool = ((HStr) entity.get("kind")).val.equals("Bool");
int count = 0;
HVal[] values = new HVal[2];
HRow row = new HRow(null, values);
while (ts.compareTo(range.end) <= 0) {
HVal val = isBool ? (HVal) HBool.make(count % 2 == 0) : (HVal) HNum.make(count);
if (ts != range.start) {
values[0] = val;
values[1] = ts;
writer.writeRow(cols, row, count++);