paradiseo/mo/tutorial/Lesson6/neutralWalk.cpp
Eremey Valetov c1a44fd2a6 Add tutorial READMEs and fix tutorial return codes
Add README.md files for moeo/tutorial/Lesson{1-4}, smp/tutorial/Lesson{1-4},
and mo/tutorial/Lesson9 — these tutorials had no documentation.

Fix return 1 → return 0 in 28 tutorial main() functions across mo/ and
smp/ that unconditionally returned failure status.
2026-02-28 19:26:10 -05:00

251 lines
8.7 KiB
C++

//-----------------------------------------------------------------------------
/** neutralWalk.cpp
*
* SV - 07/05/10
*
*/
//-----------------------------------------------------------------------------
// standard includes
#define HAVE_SSTREAM
#include <stdexcept> // runtime_error
#include <iostream> // cout
#include <sstream> // ostrstream, istrstream
#include <fstream>
#include <string.h>
// the general include for eo
#include <eo>
// declaration of the namespace
using namespace std;
//-----------------------------------------------------------------------------
// representation of solutions, and neighbors
#include <ga/eoBit.h> // bit string : see also EO tutorial lesson 1: FirstBitGA.cpp
#include <problems/bitString/moBitNeighbor.h> // neighbor of bit string
//-----------------------------------------------------------------------------
// fitness function, and evaluation of neighbors
#include <eval/royalRoadEval.h>
#include <problems/eval/moRoyalRoadIncrEval.h>
//-----------------------------------------------------------------------------
// neighborhood description
#include <neighborhood/moRndWithoutReplNeighborhood.h> // visit one random neighbor possibly the same one several times
//-----------------------------------------------------------------------------
// the sampling class
#include <utils/eoDistance.h>
#include <sampling/moNeutralWalkSampling.h>
//-----------------------------------------------------------------------------
// the statistics class
#include <sampling/moStatistics.h>
// Declaration of types
//-----------------------------------------------------------------------------
// Indi is the typedef of the solution type like in paradisEO-eo
typedef eoBit<unsigned int> Indi; // bit string with unsigned fitness type
// Neighbor is the typedef of the neighbor type,
// Neighbor = How to compute the neighbor from the solution + information on it (i.e. fitness)
// all classes from paradisEO-mo use this template type
typedef moBitNeighbor<unsigned int> Neighbor ; // bit string neighbor with unsigned fitness type
void main_function(int argc, char **argv)
{
/* =========================================================
*
* Parameters
*
* ========================================================= */
// more information on the input parameters: see EO tutorial lesson 3
// but don't care at first it just read the parameters of the bit string size and the random seed.
// First define a parser from the command-line arguments
eoParser parser(argc, argv);
// For each parameter, define Parameter, read it through the parser,
// and assign the value to the variable
// random seed parameter
eoValueParam<uint32_t> seedParam(time(0), "seed", "Random number seed", 'S');
parser.processParam( seedParam );
unsigned seed = seedParam.value();
// length of the bit string
eoValueParam<unsigned int> vecSizeParam(20, "vecSize", "Genotype size", 'V');
parser.processParam( vecSizeParam, "Representation" );
unsigned vecSize = vecSizeParam.value();
// size of the block
eoValueParam<unsigned int> blockSizeParam(4, "blockSize", "Block size of the Royal Road", 'k');
parser.processParam( blockSizeParam, "Representation" );
unsigned blockSize = blockSizeParam.value();
// the number of steps of the random walk
eoValueParam<unsigned int> stepParam(100, "nbStep", "Number of steps of the random walk", 'n');
parser.processParam( stepParam, "Representation" );
unsigned nbStep = stepParam.value();
// the name of the output file
string str_out = "out.dat"; // default value
eoValueParam<string> outParam(str_out.c_str(), "out", "Output file of the sampling", 'o');
parser.processParam(outParam, "Persistence" );
// the name of the "status" file where all actual parameter values will be saved
string str_status = parser.ProgramName() + ".status"; // default value
eoValueParam<string> statusParam(str_status.c_str(), "status", "Status file");
parser.processParam( statusParam, "Persistence" );
// do the following AFTER ALL PARAMETERS HAVE BEEN PROCESSED
// i.e. in case you need parameters somewhere else, postpone these
if (parser.userNeedsHelp()) {
parser.printHelp(cout);
exit(1);
}
if (statusParam.value() != "") {
ofstream os(statusParam.value().c_str());
os << parser;// and you can use that file as parameter file
}
/* =========================================================
*
* Random seed
*
* ========================================================= */
// reproducible random seed: if you don't change SEED above,
// you'll aways get the same result, NOT a random run
// more information: see EO tutorial lesson 1 (FirstBitGA.cpp)
rng.reseed(seed);
/* =========================================================
*
* Eval fitness function (full evaluation)
*
* ========================================================= */
// the fitness function is the royal function (oneMax is a Royal Road with block of 1)
RoyalRoadEval<Indi> fullEval(blockSize);
/* =========================================================
*
* evaluation of a neighbor solution
*
* ========================================================= */
// Incremental evaluation of the neighbor: fitness is modified by +1 , 0 or -1
moRoyalRoadIncrEval<Neighbor> neighborEval(fullEval);
/* =========================================================
*
* the neighborhood of a solution
*
* ========================================================= */
// Exploration of the neighborhood in random order
// at each step one bit is randomly generated
moRndWithoutReplNeighborhood<Neighbor> neighborhood(vecSize);
/* =========================================================
*
* The sampling of the search space
*
* ========================================================= */
// Initial Solution of the random neutral walk
Indi initialSol(vecSize, false);
// nearly 2 blocks are complete
for (unsigned i = 0; i < blockSize - 1; i++) {
initialSol[i] = true;
initialSol[blockSize + i] = true;
initialSol[2 * blockSize + i] = true;
}
// first block is complete
initialSol[blockSize - 1] = true;
// evaluation of the initial solution
fullEval(initialSol);
// Hamming distance
eoHammingDistance<Indi> distance;
// sampling object :
// - random initialization
// - neighborhood to compute the next step
// - fitness function
// - neighbor evaluation
// - number of steps of the walk
moNeutralWalkSampling<Neighbor> sampling(initialSol, neighborhood, fullEval, neighborEval, distance, nbStep);
/* =========================================================
*
* execute the sampling
*
* ========================================================= */
std::cout << "Initial Solution: " << initialSol << std::endl;
// the sampling
sampling();
/* =========================================================
*
* export the sampling
*
* ========================================================= */
// to export the statistics into file
sampling.fileExport(str_out);
// to get the values of statistics
// so, you can compute some statistics in c++ from the data
const std::vector<Indi> & solutions = sampling.getSolutions(0);
std::cout << "First values:" << std::endl;
std::cout << "Solution " << solutions[0] << std::endl;
std::cout << "Last values:" << std::endl;
std::cout << "Solution " << solutions[solutions.size() - 1] << std::endl;
// export only the solution into file
sampling.fileExport(0, str_out + "_sol");
// more basic statistics on the distribution:
moStatistics statistics;
vector< vector<double> > dist;
vector<double> v;
statistics.distances(solutions, distance, dist);
for (unsigned i = 0; i < dist.size(); i++) {
for (unsigned j = 0; j < dist.size(); j++) {
std::cout << dist[i][j] << " " ;
if (j < i)
v.push_back(dist[i][j]);
}
std::cout << std::endl;
}
double min, max, avg, std;
statistics.basic(v, min, max, avg, std);
std::cout << "min=" << min << ", max=" << max << ", average=" << avg << ", std dev=" << std << std::endl;
}
// A main that catches the exceptions
int main(int argc, char **argv)
{
try {
main_function(argc, argv);
}
catch (exception& e) {
cout << "Exception: " << e.what() << '\n';
}
return 0;
}