int ySize = matrix.size()[1];
float ySum[] = new float[ySize];
TLongFloatIterator it = matrix.vector.iterator();
for (int i = matrix.vector.size(); i-- > 0;) {
it.advance();
ySum[matrix.getIndices(it.key())[1]] += it.value();
}
it = matrix.vector.iterator();
for (int i = matrix.vector.size(); i-- > 0;) {
it.advance();
matrix.set(it.key(), it.value()