G'day Luc, On Wed, 20 May 2009 09:58:41 -0400 Luc Villandre <villa...@dms.umontreal.ca> wrote:
> MikSmith wrote: > > [...] > Indeed, functions like /lm()/ require the object fed to the /data/ > argument to be either [...] But the data argument is optional and does not need to be specified. > In your situation, I suggest you typecast your matrix into a data > frame using /as.data.frame()/. [...] My guess is that he is already working with a data frame and does not work with matrices, otherwise he should not have encountered problems: R> response <- matrix(rnorm(120), ncol=4) R> spectra.spec <- matrix(rnorm(900), ncol=30) R> spectra.lm <- lm(response[,3]~spectra.spec[,2:20]) R> spectra.lm Call: lm(formula = response[, 3] ~ spectra.spec[, 2:20]) Coefficients: (Intercept) spectra.spec[, 2:20]1 -0.48404 0.42503 spectra.spec[, 2:20]2 spectra.spec[, 2:20]3 -0.08955 -0.27605 spectra.spec[, 2:20]4 spectra.spec[, 2:20]5 -0.16832 -0.14107 spectra.spec[, 2:20]6 spectra.spec[, 2:20]7 -0.47009 -0.23672 spectra.spec[, 2:20]8 spectra.spec[, 2:20]9 0.12920 0.23306 spectra.spec[, 2:20]10 spectra.spec[, 2:20]11 -0.28586 0.03579 spectra.spec[, 2:20]12 spectra.spec[, 2:20]13 0.10676 -0.34407 spectra.spec[, 2:20]14 spectra.spec[, 2:20]15 0.20253 -0.17259 spectra.spec[, 2:20]16 spectra.spec[, 2:20]17 0.19765 0.40705 spectra.spec[, 2:20]18 spectra.spec[, 2:20]19 -0.12448 -0.17149 Cheers, Berwin ______________________________________________ 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.