clustering.cpp
#include "SFC.h"
class KeySorted {
public:
SFC::Key key;
int index;
inline bool operator<(const KeySorted& k) const {
return key < k.key;
}
};
void clustering(int n, double *weights, CkVec<TaggedVector3D> ¢ers, int procs, int *to) {
int saved_peanoKey = peanoKey;
peanoKey = 1;
// create the SFC keys
KeySorted *keys = new KeySorted[n];
for (int i=0; i<n; ++i) {
float centerArray[3];
centers[i].vec.array_form(centerArray);
keys[i].key = SFC::makeKey(centerArray);
keys[i].index = centers[i].tag;
}
sort(keys, keys+n);
// divide the keys in equal weighted segments
double sum = 0;
for (int i=0; i<n; ++i) sum += weights[i];
CkAssert(sum > 0.0);
double increment = sum / procs;
CkPrintf("sum: %f, increment: %f\n", sum, increment);
double target = increment;
double partial = 0;
int cluster = 0;
for (int i=0; i<n; ++i) {
partial += weights[keys[i].index];
to[keys[i].index] = cluster;
if (partial >= target) {
if (2*(partial-target) > weights[keys[i].index]) to[keys[i].index] ++;
cluster ++;
target += increment;
}
CkAssert(to[keys[i].index] < procs);
}
peanoKey = saved_peanoKey;
delete [] keys;
}