//---------------------------------------------------------
// Matlab "intersect" operation
//---------------------------------------------------------
IVec& intersect(const IVec& A, const IVec& B)
{
// return integer values contained in both
// A and B, sorted and without duplicates
IVec *tmp = new IVec("(A)&(B)", OBJ_temp);
int Na=A.size(), Nb=B.size(), i=0, val=0, sk=0;
if (Na<1 || Nb<1) {
// degenerate case: one array is empty
tmp->resize(0);
}
else
{
typedef std::set<int>::iterator SetIt;
// sort and remove duplicates from A and B by loading into sets
std::set<int> sA, sB, sC;
for (i=1; i<=Na; ++i) {sA.insert(A(i));} int lenA = (int) sA.size();
for (i=1; i<=Nb; ++i) {sB.insert(B(i));} int lenB = (int) sB.size();
// Use set "C" to store unique values from the
// smaller set which also occur in larger set
SetIt it, it2;
if (lenA <= lenB) {
//---------------------------------
// find values in A that occur in B
//---------------------------------
for (it=sA.begin(); it!=sA.end(); it++) {
val = (*it);
it2=sB.find(val);
if (it2 != sB.end()) {
sC.insert(val);
}
}
} else {
//---------------------------------
// find values in B that occur in A
//---------------------------------
for (it=sB.begin(); it!=sB.end(); it++) {
val = (*it);
it2=sA.find(val);
if (it2 != sA.end()) {
sC.insert(val);
}
}
}
int lenC = (int) sC.size(); tmp->resize(lenC);
for (it=sC.begin(), sk=1; it!=sC.end(); it++, sk++) {
(*tmp)(sk) = (*it);
}
}
if (A.get_mode() == OBJ_temp) { delete (&A); }
if (B.get_mode() == OBJ_temp) { delete (&B); }
return (*tmp);
}
