I using [flot](https://github.com/flot/flot) pie chart for plotting pie charts. but it shows error in firebug that

> 
> uncaught exception: Invalid dimensions for plot, width = null, height
>  = null
> 
> 
> 

I have given the height and width from stylesheet also. and tried also like this 

`<div id="placeholder1" style="width:140px;height:140px" ></div>` 

how to resolve this?