>Ed
>Now I could plot use _screen.line(1,2,3,4). I just want to move whatever I ploted from the screen to the form. What do I do that would be an easiest.
>

AFAIK, there is no line collection or array in _screen to use, and it's not like a DOS screen with a fixed number of rows and columns - the form (and this includes the main VFP Window itself) is resizable, and that size can be expressed in several different units of measure, the most common being pixels and foxels (foxels are a unit of measure unique to VFP AFAIK.) There is an X-Y coordinate system available for the current Window available through the Win32 API, but it's not trivially accessible from VFP, and would be slow to access using just native VFP.

If you're trying to get the plot output to appear on the form rather than on the main VFP window, the graphics package you use may allow you to do this, but you'll need to examine the documentation for the graphics package you're using to see how to point it at a form rather than the main VFP window; it likely will require you to extract the Windows handle for the form and pass it as a reference to the graphics package, but not knowing anything about the plotting software or how it references where it draws, it's impossible to tell you how to do this. I'm afraid you'll need to look at the documentation for the graphics package for details.