[Rcpp-devel] Maximum Columns in Rcpp DataFrame (revisited)
Hi,
thanks for the quick answer. I didn't find how to *easily*
populate my list with named elements without fiddling
with the names attribute, so I ended up creating
two dataframes and then cbinding them from within C++
Rcpp::Language("cbind", allScanHeaderInfo, allScanHeaderInfo2).eval() ;
Yours,
Steffen
On Di, 2014-07-08 at 11:17 -0500, Dirk Eddelbuettel wrote:
On 8 July 2014 at 17:51, Steffen Neumann wrote: | Hi, | | I (think I) need to create a DataFrame with more than 20 entries, | because I want another slot in this file: | https://github.com/sneumann/mzR/blob/master/src/RcppRamp.cpp#L221 | | I stumbled upon a 2year old answer here: | | http://lists.r-forge.r-project.org/pipermail/rcpp-devel/2013-March/005430.html | | Questions: | | 1) Should I avoid DataFrame here in first place ? I'd love to keep it | 2) Is there a more elegant solution for >20 entries by now ? | 3a) How do I create the mentioned "local header file with 21, 22, 23, ... \infty arguments as you need it." | 3b) How and where do I #include that ? I need to fake a directory structure | so that <Rcpp/DataFrame.h> picks up my version of #include <Rcpp/generated/DataFrame_generated.h> ? | 4) Is that future proof ?! No. Can you 'fudge it' and just create a List with N elements, each containing a DataFrame of 10 columns? You can then find them in R at the end ... Come to think of it, a DataFrame is _almost_ the same as a list, so I would just create a List with your desired 20+ elements and then just call as.data.frame() on it. Or in case all entries are numeric (you didn't say..) just take a matrix... Dirk
IPB Halle AG Massenspektrometrie & Bioinformatik Dr. Steffen Neumann http://www.IPB-Halle.DE Weinberg 3 http://msbi.bic-gh.de 06120 Halle Tel. +49 (0) 345 5582 - 1470 +49 (0) 345 5582 - 0 sneumann(at)IPB-Halle.DE Fax. +49 (0) 345 5582 - 1409 -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: This is a digitally signed message part URL: <http://lists.r-forge.r-project.org/pipermail/rcpp-devel/attachments/20140708/c2271bd6/attachment.sig>