How to interpret and modify "plot.svm"?
Dear R people, I am trying to plot the results from running svm in library(e1071). I use plot.svm. After searching through the help archives and FAQ, I still have several questions: 1. In default, crosses indicate support vectors. But why are there two colors of crosses? What do they represent? 2. I want to draw a white-gray colored plot and modify the different colored crosses or circles by different shaped points. Could anyone give me a hint? 3. Is it possible for me to draw a "hyperplane" on the plot? 4. What is the algorithm to plot the contour region? Thank you very much, Frank