Hello, Please post to the list, like this the odds for more and better answers are greater. I don't understand what you want with singlefile$GVC(singlefile$new_id[,i] singlefile$GVC is a function? How do you plot one single histogram? Post the code and maybe it will become more clear. Rui Barradas Em 18-06-2013 21:04, Dizem Uerek escreveu:> Hello > Thanks for reply > > I want to compute several histograms in a for loop.I am trying to set the binsize constant in the beginning. > > #compute the histograms > for (i in 1:12) > { > binsize <- -20 :20/2 > > hist(singlefile$GVC(singlefile$new_id[,i], freq = FALSE,xlab ="Graph i", col = "pink",main ="Example Histogram", ylim = c(-3.0,3.0))) > singlefile$GVCmin <- min(singlefile$GVC[1]) > singlefile$GVCmin <- min(singlefile$GVC[1]) > x1 <- seq(-3.0,3.0,by=.01) > lines(x1,dnorm(x1),col ="black") > } > > I tried also this but it does not do anything. I also tried your proposal , but it says that : breaks = binsize is not allowed. > > I think I am totaly far away from that what I want to do with my code . > > One single histogram plotting and computing is easy , but if it is in the loop , by the syntax to feed the function with counter i is not working > > Thanks > Dizem > Mit freundlichen Gruessen > Best Regards > Dizem Uerek >