title: generate color from number
body: <p>There is a way for get color from a number? it's mathematically possible?</p>
  
  <p>I have an array of positive number like this:</p>
  
  <p><code>array(1, 2, 1000, 564, 30, 113)</code> and I need a color (humanly distinguishable) for each of these. I can use PHP or JS for this purpose.</p>
  
  <p>I need this because i'm using <code>http://www.chartjs.org/</code> with dynamic values.</p>
  
  <p>edit:
  this is an example from chartjs documentation:</p>
  
  <pre><code>&lt;canvas id="myChart" width="400" height="400"&gt;&lt;/canvas&gt;
  &lt;script&gt;
  var ctx = document.getElementById("myChart").getContext('2d');
  var myChart = new Chart(ctx, {
      type: 'bar',
      data: {
          labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
          datasets: [{
              label: '# of Votes',
              data: [12, 19, 3, 5, 2, 3],
              backgroundColor: [
                  'rgba(255, 99, 132, 0.2)',
                  'rgba(54, 162, 235, 0.2)',
                  'rgba(255, 206, 86, 0.2)',
                  'rgba(75, 192, 192, 0.2)',
                  'rgba(153, 102, 255, 0.2)',
                  'rgba(255, 159, 64, 0.2)'
              ],
              borderColor: [
                  'rgba(255,99,132,1)',
                  'rgba(54, 162, 235, 1)',
                  'rgba(255, 206, 86, 1)',
                  'rgba(75, 192, 192, 1)',
                  'rgba(153, 102, 255, 1)',
                  'rgba(255, 159, 64, 1)'
              ],
              borderWidth: 1
          }]
      },
      options: {
          scales: {
              yAxes: [{
                  ticks: {
                      beginAtZero:true
                  }
              }]
          }
      }
  });
  &lt;/script&gt;
  </code></pre>
  
  <p>In this example are defined 6 bars (red, blue, yellow, green, purple and orange)
  In my case this bars are dynamically generated and I don't know how many bars I have to show.
  How I can associate a color for each bar? (this color must be the same everytime page refresh)</p>