Check this link...!

http://www.csie.ntu.edu.tw/~cjlin/libsvmtools/svmtoy3d/

Hello Sheema, Here i have given a sample of code in matlab which may help to you and this may give you idea for your work.

% now plot support vectors

hold on;

sv = full(model.SVs);

plot(sv(:,1),sv(:,2),'ko');

% now plot decision area

[xi,yi] = meshgrid([min(d(:,1)):0.1:max(d(:,1))],[min(d(:,2)):0.1:max(d(:,2))]);

dd = [xi(:),yi(:)];

tic;[predicted_label, accuracy, decision_values] = svmpredict(zeros(size(dd,1),1), dd, model);toc

pos = find(predicted_label==1);

hold on;

redcolor = [1 0.8 0.8];

bluecolor = [1 1 1];

h1 = plot(dd(pos,1),dd(pos,2),'s','color',redcolor,'MarkerSize',10,'MarkerEdgeColor',redcolor,'MarkerFaceColor',redcolor);

pos = find(predicted_label==-1);

hold on;

h2 = plot(dd(pos,1),dd(pos,2),'s','color',bluecolor,'MarkerSize',10,'MarkerEdgeColor',bluecolor,'MarkerFaceColor',bluecolor);

uistack(h1, 'bottom');

uistack(h2, 'bottom');

Thank you all. I have this chunck of code but I don't understand that what d and dd refers to?