HI Jim, Thanks for the help however R throws an error when i create a var tot_mon_wt- tot_mon_wt<-by(mwlc$MFST_WT,mwlc$Month,sum). It gives me an error = Error in Summary.factor(c(1L, 1L), na.rm = FALSE) : ‘sum’ not meaningful for factors
Not sure what this error refers to. Thank you, Shivi -- View this message in context: http://r.789695.n4.nabble.com/Help-on-Histogram-Barplot-tp4707739p4707744.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.