A Conditional Animation Pattern for d3 - script tag

script_tag.html

<form>
  <input id="back_detect" type="hidden" name="back_detect" value="" />
</form>

<script type="text/javascript">
  /* Render vis, animating only if value is set to "" */
  vis("#canvas", $("#back_detect").val() == "");

  /* 
   * Set the value of the form field to "visited". Most browsers will
   * preserve this when the user navigates with the back button.
   */
  $("#back_detect").val("visited");
</script>