//Runs the genetic algorithm
void Solver::runAStar()
{
for(int i=0;i<gateLimit;++i)
{
circuits.push_back(Circuit());
}
bool go = true;
int loc = -1;
unsigned long long int generation=0;
do
{
//algorithm adds new random gate every generation, and reverts if the fitness value goes lower
++generation;
addGatesAstar();
calcFitness();
revert();
runSortFitness();
cull();
loc = checkSolution();
if(generation%1000 == 0)
{
cout<<"Generation: "<<generation<<"\n";
cout<<"Num Gates: "<<circuits[0].getGateNum()<<"\n";
}
if(loc != -1)
{
solutionLoc = loc;
cout<<"Generation: "<<generation<<"\n";
go = false;
}
}while(go);
}
//Runs the genetic algorithm
//Note: Longer than 24 lines due to extensive commenting needed
void Solver::runGenetic()
{
//Uses top 20% of children
int keep = gateLimit/5;
for(int i=0;i<keep;++i)
{
circuits.push_back(Circuit());
}
addNewGates(keep);
bool go = true;
int loc = -1;
unsigned long long int generation=0;
do
{
++generation;
//Randomly deletes a gate every 100 generations
if(generation%100==0)
{
randomDelete();
}
//Gets all crosses for top 20% of children every 20 generations
if(generation%20==0)
{
crossover(keep);
}
//Mutates a Random Gate every 10 generations
if(generation%10==0)
{
mutate();
}
//Adds a new random Gate every generation
addNewGates(keep);
calcFitness();
runSortFitness();
shrink();
cull();
loc = checkSolution();
if(generation%1000 == 0)
{
cout<<"Generation: "<<generation<<"\n";
cout<<"Num Gates: "<<circuits[0].getGateNum()<<"\n";
}
if(loc != -1)
{
solutionLoc = loc;
cout<<"Generation: "<<generation<<"\n";
go = false;
}
}while(go);
}
// This routine starts with some solution (current best or a random generated
// solution) and iteratively perturb changing some nodes and applying 2OPT.
bool TSP_Perturb2OPT(TSP_Data &tsp)
{
ListGraph *g;
int nchanges,i,j;
g = &tsp.g;
vector<Node> Circuit(tsp.NNodes), BestCircuit(tsp.NNodes);
double BestCircuitValue;
//nchanges = 2 (tests with some instances indicate that nchanges=1 is better
nchanges = 1;
// Start with a initial solution (if there is no solution, generate any sequence)
if (tsp.BestCircuitValue < DBL_MAX) {
BestCircuitValue = tsp.BestCircuitValue;
for (int i=0; i<tsp.NNodes; i++) BestCircuit[i] = tsp.BestCircuit[i];
} else {
int i=0;
BestCircuitValue = 0.0;
for (ListGraph::NodeIt v(*g); v!=INVALID; ++v) BestCircuit[i++]=v;
for (i=0;i<tsp.NNodes;i++)
BestCircuitValue +=
tsp.AdjMat.Cost(BestCircuit[i] , BestCircuit[(i+1)%tsp.NNodes]);
}
for (int it=0;it<tsp.max_perturb2opt_it;it++) {
if (!(it%100)) printf("[Heuristic: Perturbation+2OPT] it = %d (of %d)\n",it+1,tsp.max_perturb2opt_it);
for (int k=0;k<tsp.NNodes;k++) Circuit[k] = BestCircuit[k];
for (int nc=0;nc<nchanges;nc++) {
i = (int) (drand48()*tsp.NNodes); // get two random nodes and exchange
j = (int) (drand48()*tsp.NNodes); // their positions
if (i!=j) ChangeNode(Circuit[i],Circuit[j]);
}
Heuristic_2_OPT(tsp.AdjMat,Circuit,BestCircuitValue,tsp.NNodes);
if (BestCircuitValue < tsp.BestCircuitValue) { //update the best circuit used
tsp.BestCircuitValue = BestCircuitValue; // by the heuristic
for (int i=0;i<tsp.NNodes;i++) {
BestCircuit[i] = Circuit[i];
tsp.BestCircuit[i] = Circuit[i];
}
}
}
return(true);
}
Circuit Netlist::create_mna_circuit() {
return Circuit(_nodes, _voltage_sources);
}
//Crosses over all pairs in the top 20% of solutions
//EX: 1 and 2, 3 and 4, etc.
//Note longer than 24 lines due to the extensive data modification needed to collect all
//10 possible crosses resulting from 2 solutions
void Solver::crossover(int k)
{
if(k%2 == 0)
{
++k;
}
for(int i=0;i<k;i+=2)
{
vector<Gate> g1 = circuits[i].getGates();
vector<Gate> g2 = circuits[i+1].getGates();
if(g1.size() >= 2 && g2.size() >= 2)
{
vector<Gate> g1h1;
vector<Gate> g1h2;
vector<Gate> g2h1;
vector<Gate> g2h2;
for(int j=0;j<g1.size()/2;++j)
{
g1h1.push_back(g1[j]);
}
for(int j=g1.size()-1;j>=g1.size()/2;--j)
{
g1h2.push_back(g1[j]);
}
for(int j=0;j<g2.size()/2;++j)
{
g2h1.push_back(g2[j]);
}
for(int j=g2.size()-1;j>=g2.size()/2;--j)
{
g2h2.push_back(g2[j]);
}
vector<vector<Gate>> crosses;
crosses.push_back(vector<Gate>(g1h1));
crosses.push_back(vector<Gate>(g2h1));
crosses.push_back(vector<Gate>(g2h1));
crosses.push_back(vector<Gate>(g1h1));
crosses.push_back(vector<Gate>(g2h2));
crosses.push_back(vector<Gate>(g2h1));
crosses.push_back(vector<Gate>(g1h1));
crosses.push_back(vector<Gate>(g1h2));
crosses.push_back(vector<Gate>(g2h2));
crosses.push_back(vector<Gate>(g1h2));
for(int j=0;j<g1h1.size();++j)
{
crosses[5].push_back(g1h1[j]);
crosses[9].push_back(g1h1[j]);
}
for(int j=0;j<g1h2.size();++j)
{
crosses[1].push_back(g1h2[j]);
crosses[2].push_back(g1h2[j]);
crosses[4].push_back(g1h2[j]);
}
for(int j=0;j<g2h1.size();++j)
{
crosses[6].push_back(g2h1[j]);
crosses[8].push_back(g2h1[j]);
}
for(int j=0;j<g2h2.size();++j)
{
crosses[0].push_back(g2h2[j]);
crosses[3].push_back(g2h2[j]);
crosses[7].push_back(g2h2[j]);
}
for(int j=0;j<crosses.size();++j)
{
circuits.push_back(Circuit(crosses[j]));
}
}
}
}
