How get the Zoom-to-fit effect when I initial the graph?

Everytime I intitial the graph,the graph’s position is terrible,Is there any way that I can get the zoom-to-fit effect when I intial the graph?

Set Diagram.InitialStretch to “Uniform”.
http://goxam.com/2.2/helpWPF/webframe.html#Northwoods.GoWPF~Northwoods.GoXam.Diagram~InitialStretch.html.

THx walter,it worked!