One way to plot subsets of data identified by a grouping variable is to use lapply() on a list of subsets. The approach is worth mentioning because similar tactics are useful for many problems.
#List of unique values for grouping variable #that is not necessarily a factor names <- as.list(unique(df$Experiment)) #List of dataframes; 1 for each unique value of grouping variable df.lst <- lapply(names,function(name)subset(df,Experiment==name)) #Name components of the list #Not necessary in this case... but permits indexing by level #of the grouping variable names(df.lst) <- names #Now you can use lapply() to carry out the same operation on #each component of your list. For example, to send plots to #a pdf with 1 page for each component: pdf("plot.pdf") lapply(df.lst,function(df)plot(df[,2],df[,3])) dev.off() ----- Glen Sargeant Research Wildlife Biologist -- View this message in context: http://n4.nabble.com/Mutliple-sets-of-data-in-one-dataset-Need-a-loop-tp1018503p1018714.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.