Files
cs5500_parallel_prog/HW10/MakePermutationMatrix.cpp
2020-04-05 16:26:24 -06:00

64 lines
2.5 KiB
C++

//
// Created by Brady Bodily on 3/28/20.
//
#include "MakePermutationMatrix.h"
#include "mpi.h"
#include <algorithm>
#include <iostream>
#include <cfloat>
long double MakePermutationMatrix::MakePermutation(std::vector<City> source, int rank, int size, std::vector<std::vector<double>> costMatrix){
std::vector<double> returnVector;
std::vector<std::size_t> localCostVector;
int vectorOffset = source.size()/size;
std::sort(source.begin(), source.end());
std::vector<City> myPerm = source;
std::vector<City> nextPerm = source;
auto lowest = LDBL_MAX;
//return vector should be the size of number of processors as they are going to only return their own smallest.
returnVector.resize(source.size(), 0);
//the "nextPerm" is the permutation to stop at.
if(rank != size-1)
std::rotate(nextPerm.begin(), nextPerm.begin() + ((rank*vectorOffset)+vectorOffset), nextPerm.end());
std::partial_sort(nextPerm.begin()+1, nextPerm.end(), nextPerm.end());
//rotate my perm.
if(rank!=0)
std::rotate(myPerm.begin(), myPerm.begin()+(((rank-1)*vectorOffset)+vectorOffset),myPerm.end());
std::partial_sort(myPerm.begin()+1, myPerm.end(), myPerm.end());
if(rank == size-1){
nextPerm = source;
}
std::cout << "Rank: " << rank << " I'm here" << std::endl;
std::cout << "Rank: " << rank << " Lowest: " << lowest << std::endl;
do {
double cost = 0;
//Add up the cost of the current permutation.
// std::cout <<"Rank: " << rank << " Current perm: ";
//std::cout << "Rank: "<< rank;
for (int i = 0; i < myPerm.size(); i++) {
//std::cout << " " << myPerm[i].GetName();
cost += costMatrix[myPerm[i].GetName()][myPerm[i-1].GetName()];
}
std::cout << "COST: " << cost <<std::endl << std::endl;
if(cost < lowest){
lowest = cost;
std::cout << "Current lowest cost: " << lowest << std::endl;
}
//Push permutation cost to the localCostVector.
//localCostVector.push_back(cost);
} while (std::next_permutation(myPerm.begin(), myPerm.end()) && myPerm!=nextPerm);
return lowest;
}
long double MakePermutationMatrix::GetLowestCost(std::vector<City> source, int rank, int size, std::vector<std::vector<double>> costMatrix){
std::vector<long double> l(size,0);
auto lowest = MakePermutation(source, rank, size, costMatrix);
MPI_Gather(&lowest,1,MPI_LONG_DOUBLE,l.data(),1,MPI_LONG_DOUBLE,0,MPI_COMM_WORLD);
std::sort(l.begin(), l.end());
return l[l.size()-1];
}