That's great thanks a lot, David! On Mon, Apr 18, 2011 at 3:47 PM, David Winsemius <dwinsem...@comcast.net> wrote: > > On Apr 18, 2011, at 3:40 PM, Dimitri Liakhovitski wrote: > >> That's helpful, thanks! Unfortunately, I cannot refer to all of my >> variables to the left of tilda one by one - I have a lot of them. >> Any way to get them in as a a bunch (somehow using mynames)? > > fmla <- as.formula(paste( > paste("`", names(example)[2:3], "`", sep="", collapse="+"), > "~group+mydate") ) > > aggregate(fmla, sum,data=example) > >> Thanks! >> >> On Mon, Apr 18, 2011 at 3:34 PM, David Winsemius <dwinsem...@comcast.net> >> wrote: >>> >>> On Apr 18, 2011, at 3:19 PM, Dimitri Liakhovitski wrote: >>> >>>> Hello! >>>> >>>> my data set has many variables. Unfortuantely, many of those variables >>>> contain spaces in their names. >>>> I need advice on: how to refer to variable names in the formula for >>>> "aggregate". See example below: >>>> >>>> ### Generating example data set: >>>> mydate = rep(seq(as.Date("2008-12-01"), length = 3, by = "month"),4) >>>> value1=c(1,10,100,2,20,200,3,30,300,4,40,400) >>>> value2=c(1.1,10.1,100.1,2.1,20.1,200.1,3.1,30.1,300.1,4.1,40.1,400.1) >>>> example<-data.frame(mydate=mydate,value1=value1,value2=value2) >>>> >>>> >>>> example$group<-c(rep("group1",3),rep("group2",3),rep("group1",3),rep("group2",3)) >>>> exampe$group<-as.factor(exampe$group) >>>> >>>> ### Generating variable names with spaces: >>>> names(example)<-c("mydate", "my value 1","my value 2","group") >>>> >>>> ### Trying to aggregate - but it's not working. Clearly, my reference >>>> to variable names is incorrect: >>>> mynames<-names(example) >>>> example.agg1<-aggregate(cbind(mynames)~group+mydate,sum,data=example) >>> >>> Use backticks: >>> >>>> aggregate(`my value 1` + `my value 2` ~group+mydate,sum,data=example) >>> >>> group mydate `my value 1` + `my value 2` >>> 1 group1 2008-12-01 8.2 >>> 2 group2 2008-12-01 12.2 >>> 3 group1 2009-01-01 80.2 >>> 4 group2 2009-01-01 120.2 >>> 5 group1 2009-02-01 800.2 >>> 6 group2 2009-02-01 1200.2 >>>> >>> >>> >>> -- >>> >>> David Winsemius, MD >>> West Hartford, CT >>> >>> >> >> >> >> -- >> Dimitri Liakhovitski >> Ninah Consulting >> www.ninah.com > > David Winsemius, MD > West Hartford, CT > >
-- Dimitri Liakhovitski Ninah Consulting www.ninah.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.