Dear R developers Using the 'foreach' package I encounter warnings like
Warning message: In identical(.combine, cbind) : ignoring non-pairlist attributes Warnings appear once in a new R-session when I run a particular piece of code - and not again. I understand from the source code of 'identical' that the function checks and believes that .combine and cbind have non-pairlist attributes, but I don't understand how this can be the case I have produced the following minimal example data.frame()[rep(1,1e6), ] library(foreach) identical(foreach:::defcombine, cbind) resulting in [1] FALSE Warning message: In identical(foreach:::defcombine, cbind) : ignoring non-pairlist attributes The warning is not related to the foreach package it seems. I get the same kind of warning with e.g. identical(spatial:::trmat, cbind) in a new R-session. Many other functions I have tried do, however, not result in the warning. The warning depends on the supposedly completely unrelated data frame operation. It seems also to be related to the fact that the data frame is empty and I extract a large number of columns out of this empty data frame. I would highly appreciate help on this to get rid of the warning in my own package. Thanks, Niels R version 2.12.1 RC (2010-12-10 r53825) Platform: i386-apple-darwin9.8.0/i386 (32-bit) locale: [1] C attached base packages: [1] stats graphics grDevices utils datasets methods base other attached packages: [1] foreach_1.3.0 codetools_0.2-6 iterators_1.0.3 (or other attached packages: [1] spatial_7.3-2) -- Niels Richard Hansen Web: www.math.ku.dk/~richard Associate Professor Email: niels.r.han...@math.ku.dk Department of Mathematical Sciences nielsrichardhan...@gmail.com University of Copenhagen Skype: nielsrichardhansen.dk Universitetsparken 5 Phone: +1 510 502 8161 2100 Copenhagen Ø Denmark ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
