Answers for "how to click a button on a page with javascript"

button click function in js

<script>
  $(document).ready(function(){
    $('#MyButton').click(function(){
       CapacityChart();
    });
  });
</script>

<input type="button" value="Capacity Chart" id="MyButton" >

html javascript button click

<button onClick="alert('some thing to say');">click</button>