Ah, the woes of English word order -- even this native English speaker frequently gets messed up!
(but maybe I'm just a bear of little brain). Best, Bert Bert Gunter Genentech Nonclinical Biostatistics (650) 467-7374 "Data is not information. Information is not knowledge. And knowledge is certainly not wisdom." Clifford Stoll On Sat, May 9, 2015 at 1:33 PM, Henrik Bengtsson <henrik.bengts...@ucsf.edu> wrote: > On Sat, May 9, 2015 at 12:55 AM, peter dalgaard <pda...@gmail.com> wrote: >> >>> On 09 May 2015, at 02:53 , Henrik Bengtsson <henrik.bengts...@ucsf.edu> >>> wrote: >>> >>> Hi, >>> >>> I spotted what looks like another(*) mistake in 'R Language >>> Definition' on how subsetting should work. In Section 'Indexing >>> matrices and arrays' >>> [http://cran.r-project.org/doc/manuals/r-release/R-lang.html#Indexing-matrices-and-arrays] >>> one can read >>> >>> "Negative indices are not allowed in indexing matrices." >> >> Parse error: I believe that this is intended to mean >> >> "Indexing matrices may not contain negative indices" >> >> not >> >> "You cannot use negative indices when indexing matrices". >> >> This is consistent with the help page: >> >> " >> A third form of indexing is via a numeric matrix with the one >> column for each dimension: each row of the index matrix then >> selects a single element of the array, and the result is a vector. >> Negative indices are not allowed in the index matrix. >> " >> >> Rephrasing would seem to be in order.... > > Ah... definitely a "parse error" (I read it as a new paragraph). I > second rephrasing this; your ""Indexing matrices may not contain > negative indices" is non-ambiguous. > > Thanks Peter > > /Henrik > >> >> -pd >> >>> >>> but this is not true, e.g. >>> >>>> x <- matrix(1:12, nrow=4) >>>> x >>> [,1] [,2] [,3] >>> [1,] 1 5 9 >>> [2,] 2 6 10 >>> [3,] 3 7 11 >>> [4,] 4 8 12 >>> >>>> x[c(-2,-4),] >>> [,1] [,2] [,3] >>> [1,] 1 5 9 >>> [2,] 3 7 11 >>> >>> /Henrik >>> >>> (*) https://stat.ethz.ch/pipermail/r-devel/2015-May/071091.html [docs >>> have been fixed] >>> >>> ______________________________________________ >>> R-devel@r-project.org mailing list >>> https://stat.ethz.ch/mailman/listinfo/r-devel >> >> -- >> Peter Dalgaard, Professor, >> Center for Statistics, Copenhagen Business School >> Solbjerg Plads 3, 2000 Frederiksberg, Denmark >> Phone: (+45)38153501 >> Email: pd....@cbs.dk Priv: pda...@gmail.com >> >> >> >> >> >> >> >> > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
