/**
* Wraps a {@link BinaryMatrix} instance with a {@link PairSet} instance.
*
* <p><b>NOTE:</b> the maximum item and transaction IDs are those existing in the binary matrix
* when the wrapping take place
*
* @param b a {@link BinaryMatrix} instance to wrap
* @return a new {@link PairSet} instance, indexed by the given matrix
*/
public static PairSet<Integer, Integer> createFromBinaryMatrix(BinaryMatrix b) {
// TODO this is a little bit costly since PairSet will allocate an array
// and a HashMap of Integers to map elements of BinaryMatrix...
// Think about a IntegerPairSet class or to an "fake" IntegerIndexedSet
// just for this purpose.
IntegerSet t = new IntegerSet(b.emptyRow());
t.intSet().add(b.maxRow() + 1);
t.intSet().complement();
IntegerSet i = new IntegerSet(b.emptyRow());
i.intSet().add(b.maxCol() + 1);
i.intSet().complement();
return new PairSet<Integer, Integer>(b, t, i);
}
