ex13.c

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/* ----------------------------------------------------------------------------
  ex13.C
  mbwall 29apr95
  Copyright (c) 1995-1996  Massachusetts Institute of Technology

 DESCRIPTION:
  This example illustrates the use of a GA-within-a-GA.  It uses a steady
state GA to find the smiley face, then it uses another steady state GA to match
a sequence of random numbers.  It doesn't try to do the random numbers until
it has gotten 90% of the way to the smiley face.
  This is very similar in function to the composite genome example, but 
here we evolve the two genomes separately rather than as a single entity.
  This kind of application can be useful for situations where the computational
cost of calculating feasibility is rather high and the feasible space is 
sparse.
---------------------------------------------------------------------------- */
#include <stdio.h>
#include <stdlib.h>
#include <iostream.h>
#include <fstream.h>
#include <math.h>
#include <ga/ga.h>


typedef struct _UserData {
  int width, height;
  short **picture_target;
  float *numbers_target;
  GA2DBinaryStringGenome *picture_genome;
  GABin2DecGenome *numbers_genome;
} UserData;

float PictureObjective(GAGenome &);
float NumbersObjective(GAGenome &);

int
main(int argc, char *argv[])
{
  cout << "Example 13\n\n";
  cout << "This program runs a GA-within-GA.  The outer level GA tries to\n";
  cout << "match the pattern read in from a file.  The inner level GA is\n";
  cout << "run only when the outer GA reaches a threshhold objective score\n";
  cout << "then it tries to match a sequence of numbers that were generated\n";
  cout << "randomly at the beginning of the program's execution.\n\n";
  cout << "You might have to run the primary GA for more than 5000\n";
  cout << "generations to get a score high enough to kick in the secondary\n";
  cout << "genetic algorithm.  Use the ngen option to do this on the\n";
  cout << "command line.\n\n";

// See if we've been given a seed to use (for testing purposes).  When you
// specify a random seed, the evolution will be exactly the same each time
// you use that seed number.

  unsigned int seed = 0;
  for(int ii=1; ii<argc; ii++) {
    if(strcmp(argv[ii++],"seed") == 0) {
      seed = atoi(argv[ii]);
    }
  }

  char filename[128] = "smiley.txt";

// Set the default values of the parameters and declare the params variable.

  int i,j;
  GAParameterList params;
  GAIncrementalGA::registerDefaultParameters(params);
  params.set(gaNpopulationSize, 150);
  params.set(gaNpCrossover, 0.8);
  params.set(gaNpMutation, 0.005);
  params.set(gaNnGenerations, 500);
  params.set(gaNscoreFilename, "bog.dat");
  params.set(gaNscoreFrequency, 10);
  params.set(gaNflushFrequency, 50);
  params.parse(argc, argv, gaFalse);   // don't complain about unknown args

// Create a user data object.  We'll keep all of the information for this 
// program in this object.
  UserData data;

// Read in the pattern from the specified file.  File format is pretty simple:
// two integers that give the height then width of the matrix, then the matrix
// of 1's and 0's (with whitespace inbetween).

  ifstream inStream(filename, ios :: in);
  if(!inStream){
    cerr << "Cannot open " << filename << " for input.\n";
    exit(1);
  }
  inStream >> data.height >> data.width;
  data.picture_target = new short*[data.width];
  for(i=0; i<data.width; i++)
    data.picture_target[i] = new short[data.height];
  for(j=0; j<data.height; j++)
    for(i=0; i<data.width; i++)
      inStream >> data.picture_target[i][j];
  inStream.close();

// Print out the pattern to be sure we got the right one.

  cout << "input pattern:\n";
  for(j=0; j<data.height; j++){
    for(i=0; i<data.width; i++)
      cout << (data.picture_target[i][j] == 1 ? '*' : ' ') << " ";
    cout << "\n";
  }
  cout << "\n"; cout.flush();

// Generate the random sequence of numbers.

  int n=7;
  float min[] = {0, 0,   3, -5, 100,    0.001, 0};
  float max[] = {1, 100, 3, -2, 100000, 0.010, 7};
  GARandomSeed(seed);
  data.numbers_target = new float[n];
  for(i=0; i<n; i++)
    data.numbers_target[i] = GARandomFloat(min[i], max[i]);
  data.numbers_target[6] = GARandomInt((int)min[6], (int)max[6]);

// Print out the sequence so we'll know what we have to match.

  cout << "input sequence:\n";
  for(i=0; i<n; i++){
    cout.width(10);
    cout << data.numbers_target[i] << " ";
  }
  cout << "\n"; cout.flush();


// Create a phenotype for the numbers to map them to a bin2dec genome.

  GABin2DecPhenotype map;
  for(i=0; i<n; i++)
    map.add(8, min[i], max[i]);

// Create a couple of genomes for keeping track in our user data.
  data.picture_genome = new GA2DBinaryStringGenome(data.width, data.height,
						   PictureObjective, 
						   (void *)&data);
  data.numbers_genome = new GABin2DecGenome(map,
					    NumbersObjective, 
					    (void *)&data);

// Now create the GA and run it.

  GA2DBinaryStringGenome picture_genome(*(data.picture_genome));
  GABin2DecGenome numbers_genome(*(data.numbers_genome));
  GAIncrementalGA ga(picture_genome);
  ga.parameters(params);
  ga.evolve();

// Now that we have evolved the best solution, put the best into our genomes
// then print them out.

  picture_genome = ga.statistics().bestIndividual();
  cout << "the ga generated:\n";
  for(j=0; j<data.height; j++){
    for(i=0; i<data.width; i++)
      cout << (picture_genome.gene(i,j) == 1 ? '*' : ' ') << " ";
    cout << "\n";
  }
  cout << "\n"; cout.flush();

 numbers_genome = *data.numbers_genome;
  for(i=0; i<map.nPhenotypes(); i++){
    cout.width(10);
    cout << numbers_genome.phenotype(i) << " ";
  }
  cout << "\n\n"; cout.flush();

  cout << "best of generation data are in '" << ga.scoreFilename() << "'\n";


// free up all of the space we were using.

  for(i=0; i<data.width; i++)
    delete data.picture_target[i];
  delete [] data.picture_target;
  delete [] data.numbers_target;

  delete data.picture_genome;
  delete data.numbers_genome;

  return 0;
}
 




// This is the primary objective function.  If it gets a genome whose score
// is sufficiently high, then it runs another GA on the number sequence and
// returns a composite score.
float
PictureObjective(GAGenome & c)
{
  GA2DBinaryStringGenome & genome = (GA2DBinaryStringGenome &)c;
  UserData * data = (UserData *)c.userData();

  float value=0.0;
  for(int i=0; i<genome.width(); i++)
    for(int j=0; j<genome.height(); j++)
      value += (float)(genome.gene(i,j) == data->picture_target[i][j]);

  float correct = value / ((float)genome.width() * (float)genome.height());

  // if we get at least 95% of the pixels right, then run the secondary ga.

  if(correct > 0.95) {
    GABin2DecGenome& num_genome = (GABin2DecGenome&)(*data->numbers_genome);
    GAIncrementalGA ga(num_genome);
    ga.populationSize(550);
    ga.nGenerations(50);
    ga.pMutation(0.01);
    ga.pCrossover(0.9);
    ga.evolve();
    *data->numbers_genome = ga.statistics().bestIndividual();

    correct += data->numbers_genome->score();
  }

  return correct;
}


// This is the objective function for matching the sequence of numbers.
float
NumbersObjective(GAGenome & c)
{
  GABin2DecGenome & genome = (GABin2DecGenome &)c;
  UserData * data = (UserData *)c.userData();

  float value=genome.nPhenotypes();
  for(int i=0; i<genome.nPhenotypes(); i++)
    value += 1.0 / (1.0 + fabs(genome.phenotype(i) - data->numbers_target[i]));

  value /= genome.nPhenotypes();

  return value;
}