title: Update via mouseover in google charts
body: <p>I'm using Google charts to interactively draw some data. </p>
  
  <p>I want to draw two charts. The first chart plots f(x) vs. x. The second chart plots g(x,y) vs. y (for a fixed value x). On mouseover for the first chart, the x value will be used to redraw g(x,y) vs. y. </p>
  
  <p>For example, on mouseover of x=1 on the first chart, the second chart would refresh, drawing g(1,y) vs. y. </p>
  
  <p>The only way I've been able to accomplish this was to manually bind the mouseover event in javascript, and trigger a full redraw of the second chart (by erasing its data and copying in data with the moused over x value). However, there is a built-in mechanism to redraw the chart using values from controls (e.g. a slider, <a href="http://code.google.com/apis/ajax/playground/?type=visualization#simple_dashboard" rel="nofollow">example here</a>).</p>
  
  <p>Does anyone know if there is a way to bind two charts so that the mouseover event can be used to redraw one chart with new parameters?</p>