Hi Camille, Probably you have to check wether there is any infinte value in x.
Or calculate something like that for your x-axis: x[1:(ll-1)]+diff(x)/2 Regards, Pascal ----- Mail original ----- De : Camille Leclerc <camille.lecl...@ymail.com> À : r-help@r-project.org Cc : Envoyé le : Lundi 26 mars 2012 0h32 Objet : Re: [R] ROC Analysis Hi everybody, Pascal, your code works, but when I want to do the graph I have an error message. here is my code : x<-rev(unlist(pred@cutoffs)) tpf<-unlist(performance(pred, "tpr")@y.values) fpf<-unlist(performance(pred,"fpr")@y.values) ll<-length(x) p<-(tpf[1:(ll-1)]-tpf[2:ll])/(fpf[1:(ll-1)]-fpf[2:ll]) plot(x,p) *Erreur dans xy.coords(x, y, xlabel, ylabel, log) : 'x' and 'y' lengths differ* So, when I look the lenghts of x and p, I have this : *x : numeric[1735] p : numeric[1734]* On the other hand, it's normal since I have the slope between two points on the ROC curve and so I have x points and x-1 slope values. How to get the graph?! All the best, Camille ----- -- Camille Leclerc, Master student Lab ESE, UMR CNRS 8079 Univ Paris-Sud Bat 362 F-91405 Orsay Cedex FRANCE -- View this message in context: http://r.789695.n4.nabble.com/ROC-Analysis-tp4469203p4503354.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
