final int univSize = universe().size();
if (c==Expression.UNIV) {
final IntSet all = Ints.rangeSet(Ints.range(0, univSize-1));
return factory().matrix(Dimensions.square(univSize, 1), all, all);
} else if (c==Expression.IDEN) {
final Dimensions dim2 = Dimensions.square(univSize, 2);
final IntSet iden = Ints.bestSet(dim2.capacity());
for(int i = 0; i < univSize; i++) {
iden.add(i*univSize + i);
}
return factory().matrix(dim2, iden, iden);
} else if (c==Expression.NONE) {