for example
if the page contains
<epiviz-environment id="env">
</epiviz-environment>
to add an epiviz chart for example line-track.
elem = document.createElement('epiviz-line-track');
elem.dimS = ['affy1', 'affy2'];
elem.dimX = 'affy1';
elem.dimY = 'affy2';
elem.className="charts"
ot = document.querySelector('#env')
Polymer.dom(ot).appendChild(elem)