Probability Demo Source

<script language="JavaScript" type="text/JavaScript">
//<![CDATA[
var evolved = false;
var genX;
var genY;
 
function Create()
{
  genX = new Array(100); // Create an array of 100 creatures
  genY = new Array(100); // Create an array of 100 creatures
  for (i = 0; i < 100; ++i) // Go through the population
  {
    genX[i] = new Array(6); // Create 5 genes for each creature
    genY[i] = new Array(6); // Create 5 genes for each creature
    for (gene = 0; gene < 5; ++gene) // Go through each gene for each creature
    {
      genX[i][gene] = 0; // Assign each gene a starting value
    }
  }
}
function Mutate(gen)
{
  for (i = 0; i < 100; ++i) // Go through the population
    {
      for (gene = 0; gene < 5; ++gene) // Go through each gene for each creature
      {
        if (Math.round(100*Math.random()) == 42) // Take a 1 in 100 shot
        {
          if (gen[i][gene] == 0) // Mutate this gene
            gen[i][gene] = 1
          else
            gen[i][gene] = 0;
        }
      }
   }
}
function Maxfitness(gen)
{
  var fitness;
  var maxfitness = 0;
  for (i = 0; i < 100; ++i) // Go through the population
  {
    fitness = 0;
    for (gene = 0; gene < 5; ++gene) // Go through each gene for each creature
    {
      if (gen[i][gene] == 1)
      {
        ++fitness;
      }
    }
    gen[i][5] = fitness;
    document.write(fitness);
    if (fitness > maxfitness)
    {
      maxfitness = fitness;
      if (maxfitness == 5)
      {
        evolved = true;
      }
    }
  }
  return(maxfitness);
}
function Reproduce(gen, nextgen)
{
  var maxfitness = Maxfitness(gen);
  var k = 0;
  for (i = 0; i < 100; i++)
  {
    if (gen[i][5] == maxfitness)
    {
      for (gene = 0; gene < 5; gene++)
      {
        nextgen[k][gene] = gen[i][gene];
      }
      k++;
      if (k == 100)
      {
        return;
      }
      for (gene = 0; gene < 5; gene++)
      {
        nextgen[k][gene] = gen[i][gene];
      }
      k++;
      if (k == 100)
      {
        return;
      }
    }
  }
  for (i = 0; i < 100; i++)
  {
    if (gen[i][5] != maxfitness)
    {
      for (gene = 0; gene < 5; gene++)
      {
        nextgen[k][gene] = gen[i][gene];
      }
      k++;
      if (k == 100)
      {
        return;
      }
    }
  }
}
function Run()
{
  Create();
  while (evolved == false)
  {
    Mutate(genX);
    Reproduce(genX, genY);
    document.write("<br />");
    if (evolved == false)
    {
      Mutate(genY);
      Reproduce(genY, genX);
    }
    document.write("<br />");
  }
}
Run();
//]]>
</script>