Hi: Here's the problem:
> str(fun3) 'data.frame': 4 obs. of 3 variables: $ sector :'data.frame': 4 obs. of 1 variable: ..$ gics_sector_name: chr "Financials" "Financials" "Materials" "Materials" $ bebitpcchg: num -0.567 0.996 NA -42.759 $ ticker : chr "UBSN VX Equity" "LLOY LN Equity" "AI FP Equity" "AKE FP Equity" Notice that fun3$sector is a data frame, not a variable. By leaving fun3 intact, the summary is gotten with ddply(fun3, .(sector$gics_sector_name), summarise, avgbebitchg=mean(bebitpcchg,na.rm=TRUE)) sector$gics_sector_name avgbebitchg 1 Financials 0.2142787 2 Materials -42.7587479 You might consider reframing fun3, pardon the pun. HTH, Dennis On Sat, Oct 1, 2011 at 7:58 AM, Aidan Corcoran <aidan.corcora...@gmail.com> wrote: > Dear list, > > I encounter an error when I try to use ddply to generate means as follows: > > fun3<-structure(list(sector = structure(list(gics_sector_name = > c("Financials", > "Financials", "Materials", "Materials")), .Names = "gics_sector_name", > row.names = structure(c("UBSN VX Equity", > "LLOY LN Equity", "AI FP Equity", "AKE FP Equity"), .Dim = 4L), class > = "data.frame"), > bebitpcchg = c(-0.567449058550428, 0.99600643852127, NA, > -42.7587478692081), ticker = c("UBSN VX Equity", "LLOY LN Equity", > "AI FP Equity", "AKE FP Equity")), .Names = c("sector", "bebitpcchg", > "ticker"), row.names = c(12L, 24L, 36L, 48L), class = "data.frame") > > fun3 > > gics_sector_name bebitpcchg ticker > 12 Financials -0.5674491 UBSN VX Equity > 24 Financials 0.9960064 LLOY LN Equity > 36 Materials NA AI FP Equity > 48 Materials -42.7587479 AKE FP Equity > > > fun4<-ddply(fun3,c("sector"),summarise,avgbebitchg=mean(bebitpcchg,na.rm=TRUE)) > > Error in `[.data.frame`(x, order(x, na.last = na.last, decreasing = > decreasing)) : > undefined columns selected > > This is a small sample of my data. I’m probably overlooking some > problem in my syntax, but would be very grateful if someone could > point it out. > > Thanks in advance, > Aidan. > > sessionInfo() > > R version 2.13.0 (2011-04-13) > Platform: i386-pc-mingw32/i386 (32-bit) > > locale: > [1] LC_COLLATE=English_Ireland.1252 LC_CTYPE=English_Ireland.1252 > LC_MONETARY=English_Ireland.1252 > [4] LC_NUMERIC=C LC_TIME=English_Ireland.1252 > > attached base packages: > [1] grid stats graphics grDevices utils datasets > methods base > > other attached packages: > [1] plm_1.2-7 sandwich_2.2-7 MASS_7.3-12 > Formula_1.0-1 nlme_3.1-100 > [6] bdsmatrix_1.0 RBloomberg_0.4-149 rJava_0.8-8 > gtools_2.6.2 gdata_2.8.2 > [11] ggplot2_0.8.9 proto_0.3-9.2 zoo_1.7-4 > reshape_0.8.4 plyr_1.6 > > loaded via a namespace (and not attached): > [1] lattice_0.19-23 tools_2.13.0 > > ______________________________________________ > 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. > ______________________________________________ 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.