How to plot roc curve for multi class?

I have 3 classes and i want to plot roc curve for my classifier. But by using plotroc it is plotting only for binary class. I can't understand how to plot for multi class.

Answer 1

[Jagadeeswararao Annam]

ROC curve is done for binary classification. For Multi-class you have to create 3 one-vs-rest binary classifications on data taking positive samples as 1 and negative samples as -1.