Project-4/src/phase_transition_mpi.cpp

109 lines
3.1 KiB
C++

/** @file phase_transition_mpi.cpp
*
* @author Cory Alexander Balaton (coryab)
* @author Janita Ovidie Sandtrøen Willumsen (janitaws)
*
* @version 1.0
*
* @brief Sweep over different temperatures and generate data.
*
* @bug No known bugs
* */
#include "data_type.hpp"
#include "monte_carlo.hpp"
#include "utils.hpp"
#include <algorithm>
#include <fstream>
#include <iostream>
#include <iterator>
#include <mpi.h>
/** @brief The main function*/
int main(int argc, char **argv)
{
double start = 1., end = 3.;
uint points = 1000, L = 20, N;
double dt = (end - start) / points;
uint cycles = 10000;
N = L * L;
std::ofstream ofile;
data_t data[points];
// MPI stuff
int rank, cluster_size;
// Initialize MPI
MPI_Init(&argc, &argv);
// Get the cluster size and rank
MPI_Comm_size(MPI_COMM_WORLD, &cluster_size);
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
uint remainder = points % cluster_size;
double i_start;
uint i_points;
// The last
if (rank < remainder) {
i_points = points / cluster_size + 1;
i_start = start + dt * i_points * rank;
}
else {
i_points = points / cluster_size;
i_start = start + dt * (i_points * rank + remainder);
}
data_t i_data[i_points];
std::cout << "Rank " << rank << ": " << i_points << ',' << i_start << '\n';
for (size_t i = 0; i < i_points; i++) {
monte_carlo_serial(i_data[i], L, i_start + dt * i, cycles);
}
if (rank == 0) {
std::copy_n(i_data, i_points, data);
for (size_t i = 1; i < cluster_size; i++) {
if (rank < remainder) {
MPI_Recv((void *)i_data,
sizeof(data_t) * (points / cluster_size + 1), MPI_CHAR,
i, MPI_ANY_TAG, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
std::copy_n(i_data, points / cluster_size + 1,
data + (points / cluster_size) * i);
}
else {
MPI_Recv((void *)i_data,
sizeof(data_t) * (points / cluster_size), MPI_CHAR, i,
MPI_ANY_TAG, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
std::copy_n(i_data, points / cluster_size,
data + (points / cluster_size) * i + remainder);
}
}
}
else {
MPI_Send(i_data, i_points * sizeof(data_t), MPI_CHAR, 0, rank,
MPI_COMM_WORLD);
}
MPI_Finalize();
std::string outfile = "output/phase_transition/size_20.txt";
utils::mkpath(utils::dirname(outfile));
ofile.open(outfile);
double temp, CV, X;
using utils::scientific_format;
for (size_t i = 0; i < points; i++) {
temp = start + dt * i;
CV = (data[i].E2 - data[i].E * data[i].E) / (N * temp * temp);
X = (data[i].M2 - data[i].M_abs * data[i].M_abs) / (N * temp);
ofile << scientific_format(temp) << ','
<< scientific_format(data[i].E / N) << ','
<< scientific_format(data[i].M_abs / N) << ','
<< scientific_format(CV) << ',' << scientific_format(X) << '\n';
}
ofile.close();
}