You need to use "==" instead of "=" for testing equality. While you're at it, you should check for positive values, not just screening out 0s. This works for me:
R> mydata = data.frame(x=0:10, y=runif(11)) R> fm = lm(y ~ log(x), mydata, subset=x>0) Andy > -----Original Message----- > From: r-help-boun...@r-project.org > [mailto:r-help-boun...@r-project.org] On Behalf Of agent dunham > Sent: Friday, February 25, 2011 6:24 AM > To: r-help@r-project.org > Subject: [R] lm - log(variable) - skip log(0) > > > > I want to do a lm regression, some of the variables are going > to be affected > with log, I would like not no take into account the values > which imply doing > log(0) > > for just one variable I have done the following but it doesn't work: > > lmod1.lm <- > lm(log(dat$inaltu)~log(dat$indiam),subset=(!(dat$indiam %in% > c(0,1))) > > and obtain: > > Error en lm.fit(x, y, offset = offset, singular.ok = > singular.ok, ...) : > 0 (non-NA) cases > > lmod1.lm <- > lm(log(dat$inaltu)~log(dat$indiam),subset=(!(dat$indiam = 0)), > na.action=na.exclude) > > and obtain > > Error en lm.fit(x, y, offset = offset, singular.ok = > singular.ok, ...) : > NA/NaN/Inf en llamada a una función externa (arg 1) > > Thanks, u...@host.com > -- > View this message in context: > http://r.789695.n4.nabble.com/lm-log-variable-skip-log-0-tp332 4263p3324263.html > Sent from the R help mailing list archive at Nabble.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. > Notice: This e-mail message, together with any attachme...{{dropped:11}} ______________________________________________ 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.
