public void eachNonZeroInRow(int i, MatrixProcedure procedure, int fromColumn, int toColumn) {
ByteVectorIterator it = nonZeroRowIterator(i, fromColumn, toColumn);
while (it.hasNext()) {
it.next();
procedure.apply(i, it.index(), it.get());
}
}
@Override
public void eachNonZeroInColumn(int j, MatrixProcedure procedure) {