// select mPopulationSize individuals
bool COptMethodGA::select()
{
unsigned C_INT32 i, j, nopp, opp;
unsigned C_INT32 TotalPopulation = 2 * mPopulationSize;
// tournament competition
mLosses = 0; // Set all wins to 0.
// compete with ~ 20% of the TotalPopulation
nopp = std::max<unsigned C_INT32>(1, mPopulationSize / 5);
// parents and offspring are all in competition
for (i = 0; i < TotalPopulation; i++)
for (j = 0; j < nopp; j++)
{
// get random opponent
opp = mpRandom->getRandomU(TotalPopulation - 1);
if (mValue[i] < mValue[opp])
mLosses[opp]++;
else
mLosses[i]++;
}
// selection of top mPopulationSize winners
partialSortWithPivot(mLosses.array(),
mLosses.array() + mPopulationSize,
mLosses.array() + TotalPopulation,
mPivot);
FSwapClass<COptMethodGA, unsigned C_INT32, bool> Swap(this, &COptMethodGA::swap);
applyPartialPivot(mPivot, mPopulationSize, Swap);
return true;
}
bool COptMethodEP::select()
{
size_t i, j, nopp, opp;
size_t TotalPopulation = 2 * mPopulationSize;
// tournament competition
mLosses = 0; // Set all losses to 0.
// compete with ~ 20% of the TotalPopulation
nopp = std::max<size_t>(1, mPopulationSize / 5);
// parents and offspring are all in competition
for (i = 0; i < TotalPopulation; i++)
for (j = 0; j < nopp; j++)
{
// get random opponent
do
{
opp = mpRandom->getRandomU((unsigned C_INT32)(TotalPopulation - 1));
}
while (i == opp);
if (mValue[i] < mValue[opp])
mLosses[opp]++;
else
mLosses[i]++;
}
partialSortWithPivot(mLosses.array(),
mLosses.array() + mPopulationSize,
mLosses.array() + TotalPopulation,
mPivot);
FSwapClass<COptMethodEP, size_t, bool> Swap(this, &COptMethodEP::swap);
applyPartialPivot(mPivot, mPopulationSize, Swap);
return true;
}
