Genetic.js Hello World

Use Genetic.js, be happy.

<!DOCTYPE html>
<head>
  <meta charset="utf-8">
  <script src="https://d3js.org/d3.v4.min.js"></script>
  <script src="https://unpkg.com/genetic-js"></script>
  <style>
    body { margin:0;position:fixed;top:0;right:0;bottom:0;left:0; font-family: monospace; }
    td {
      border: solid 0.5px #eee;
    }
  </style>
</head>

<body>
  <table><thead><th>Generation</th><th>Fitness</th><th>Best Individual</th></thead><tbody>
  </tbody></table>
  <script>
    // Feel free to change or delete any of the code you see in this editor!
     var genetic = Genetic.create();

genetic.optimize = Genetic.Optimize.Maximize;
genetic.select1 = Genetic.Select1.Tournament2;
genetic.select2 = Genetic.Select2.Tournament2;

genetic.seed = function() {

function randomString(len) {
        var text = "";
        var charset = "abcdefghijklmnopqrstuvwxyz0123456789";
        for(var i=0;i<len;i++)
            text += charset.charAt(Math.floor(Math.random() * charset.length));
        
        return text;
    }
    
    // create random strings that are equal in length to solution
    return randomString(this.userData["solution"].length);
};

genetic.mutate = function(entity) {
    
    function replaceAt(str, index, character) {
        return str.substr(0, index) + character + str.substr(index+character.length);
    }
    
    // chromosomal drift
    var i = Math.floor(Math.random()*entity.length)     
    return replaceAt(entity, i, String.fromCharCode(entity.charCodeAt(i) + (Math.floor(Math.random()*2) ? 1 : -1)));
};

genetic.crossover = function(mother, father) {

// two-point crossover
    var len = mother.length;
    var ca = Math.floor(Math.random()*len);
    var cb = Math.floor(Math.random()*len);     
    if (ca > cb) {
        var tmp = cb;
        cb = ca;
        ca = tmp;
    }
        
    var son = father.substr(0,ca) + mother.substr(ca, cb-ca) + father.substr(cb);
    var daughter = mother.substr(0,ca) + father.substr(ca, cb-ca) + mother.substr(cb);
    
    return [son, daughter];
};

genetic.fitness = function(entity) {
    var fitness = 0;
    
    var i;
    for (i=0;i<entity.length;++i) {
        // increase fitness for each character that matches
        if (entity[i] == this.userData["solution"][i])
            fitness += 1;
        
        // award fractions of a point as we get warmer
        fitness += (127-Math.abs(entity.charCodeAt(i) - this.userData["solution"].charCodeAt(i)))/50;
    }

return fitness;
};

genetic.generation = function(pop, generation, stats) {
    // stop running once we've reached the solution
    return pop[0].entity != this.userData["solution"];
};

genetic.notification = function(pop, generation, stats, isFinished) {

console.log(stats);
    function lerp(a, b, p) {
        return a + (b-a)*p;
    }
    
    var value = pop[0].entity;
    this.last = this.last||value;
    
    if (pop != 0 && value == this.last)
        return;
    
    
    var solution = [];
    var i;
    for (i=0;i<value.length;++i) {
        var diff = value.charCodeAt(i) - this.last.charCodeAt(i);
        var style = "background: transparent;";
        if (diff > 0) {
            style = "background: rgb(0,200,50); color: #fff;";
        } else if (diff < 0) {
            style = "background: rgb(0,100,50); color: #fff;";
        }

solution.push("<span style=\"" + style + "\">" + value[i] + "</span>");
    }
    
    var buf = "";
    buf += "<td>" + generation + "</td>";
    buf += "<td>" + pop[0].fitness.toPrecision(5) + "</td>";
    buf += "<td>" + solution.join("") + "</td>";
    d3.select("tbody").insert("tr", "*").html(buf);
    
    this.last = value;
};

var config = {
            "iterations": 4000
            , "size": 250
            , "crossover": 0.3
            , "mutation": 0.3
            , "skip": 50
            , "webWorkers" : true
        };

genetic.evolve(config, { solution: 'Mimeme comes from a suitable Greek root, but I want a monosyllable that sounds a bit like gene' });

</script>
</body>

https://d3js.org/d3.v4.min.js

https://unpkg.com/genetic-js