Hi all, this is a reoccurring theme in my programming and I need some help with it. When I use a built in function and need to use it on a subset of my data frame, I always end up using the subset function first, but this seems very clunky. For example, if I have years 2003:2013 with season "a" and "b" within each year, and I want to create a smooth.spline, I end up creating a subset for each year and season, and then have a smooth spline function for each year and season. Can I do this more efficiently?
The subsets are below: size.2003<-subset(size,Year==2003&Season=="a") size.2004<-subset(size,Year==2004&Season=="a") size.2005<-subset(size,Year==2005&Season=="a") size.2006<-subset(size,Year==2006&Season=="a") size.2007<-subset(size,Year==2007&Season=="a") size.2008<-subset(size,Year==2008&Season=="a") size.2009<-subset(size,Year==2009&Season=="a") size.2010<-subset(size,Year==2010&Season=="a") size.2011<-subset(size,Year==2011&Season=="a") size.2012<-subset(size,Year==2012&Season=="a") size.2013<-subset(size,Year==2013&Season=="a") size.2003b<-subset(size,Year==2003&Season=="b") size.2004b<-subset(size,Year==2004&Season=="b") size.2005b<-subset(size,Year==2005&Season=="b") size.2006b<-subset(size,Year==2006&Season=="b") size.2007b<-subset(size,Year==2007&Season=="b") size.2008b<-subset(size,Year==2008&Season=="b") size.2009b<-subset(size,Year==2009&Season=="b") size.2010b<-subset(size,Year==2010&Season=="b") size.2011b<-subset(size,Year==2011&Season=="b") size.2012b<-subset(size,Year==2012&Season=="b") size.2013b<-subset(size,Year==2013&Season=="b") The smooth.spline is below 2003<-with(size.2003,smooth.spline(Size,Prop,spar=0.25)) 2004<-with(size.2004,smooth.spline(Size,Prop,spar=0.25)) 2005<-with(size.2005,smooth.spline(Size,Prop,spar=0.25)) etc. etc. M. Keith Cox, Ph.D. Principal MKConsulting 17105 Glacier Hwy Juneau, AK 99801 U.S. 907.957.4606 [[alternative HTML version deleted]] ______________________________________________ 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.