Dynamically Re-generate a Pivot Chart

Dynamically Re-generate a Pivot Chart

I have a pivot chart that I would like to call through a "Custom Action" button that calls a function containing the OpenUrl.  My question is, since data in the reports (i.e., Pivot tables, Pivot charts) are not automatically updated, how do I dynamically Re-generate the chart to refresh the new data through the script and without pressing on the little "gear" and clicking re-generate??

Thank you for your help