Re: [Rd] incorrect result (41/10-1/10)%%1 (PR#13863)
> I get an incorrect result for > > (41/10-1/10)%%1 > > [1] 1 Note that due to rounding errors, 41/10-1/10 is formatC(41/10-1/10, digits=20) # [1] "3.9995559" Besides FAQ 7.31, related information may be found also at http://wiki.r-project.org/rwiki/doku.php?id=misc:r_accuracy Petr. __ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
Re: [Rd] incorrect result (41/10-1/10)%%1 (PR#13863)
Good morning Jan, Could this be covered off by the following? http://cran.r-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f Kind regards, Sean On Sat, Aug 1, 2009 at 9:05 PM, wrote: > Full_Name: jan hattendorf > Version: 2.9.0 > OS: XP > Submission from: (NULL) (213.3.108.185) > > > I get an incorrect result for > > (41/10-1/10)%%1 > > [1] 1 > > The error did not occur with other numbers than 41 (1, 11, 21, 31, 51, ...) > > > test <- rep(NA, 1000) > for(i in 1:1000){ > test[i] <- i/10-1/10 > } > test[test%%1==0] > > __ > 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
Re: [Rd] incorrect result (41/10-1/10)%%1 (PR#13863)
This is not a bug. It is a case of R FAQ 7.34: http://cran.r-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-think-the se-numbers-are-equal_003f ir. Thierry Onkelinx Instituut voor natuur- en bosonderzoek / Research Institute for Nature and Forest Cel biometrie, methodologie en kwaliteitszorg / Section biometrics, methodology and quality assurance Gaverstraat 4 9500 Geraardsbergen Belgium tel. + 32 54/436 185 thierry.onkel...@inbo.be www.inbo.be To call in the statistician after the experiment is done may be no more than asking him to perform a post-mortem examination: he may be able to say what the experiment died of. ~ Sir Ronald Aylmer Fisher The plural of anecdote is not data. ~ Roger Brinner The combination of some data and an aching desire for an answer does not ensure that a reasonable answer can be extracted from a given body of data. ~ John Tukey -Oorspronkelijk bericht- Van: r-devel-boun...@r-project.org [mailto:r-devel-boun...@r-project.org] Namens jan.hattend...@unibas.ch Verzonden: zaterdag 1 augustus 2009 22:05 Aan: r-de...@stat.math.ethz.ch CC: r-b...@r-project.org Onderwerp: [Rd] incorrect result (41/10-1/10)%%1 (PR#13863) Full_Name: jan hattendorf Version: 2.9.0 OS: XP Submission from: (NULL) (213.3.108.185) I get an incorrect result for (41/10-1/10)%%1 [1] 1 The error did not occur with other numbers than 41 (1, 11, 21, 31, 51, ...) test <- rep(NA, 1000) for(i in 1:1000){ test[i] <- i/10-1/10 } test[test%%1==0] __ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel Dit bericht en eventuele bijlagen geven enkel de visie van de schrijver weer en binden het INBO onder geen enkel beding, zolang dit bericht niet bevestigd is door een geldig ondertekend document. The views expressed in this message and any annex are purely those of the writer and may not be regarded as stating an official position of INBO, as long as the message is not confirmed by a duly signed document. __ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
Re: [Rd] incorrect result (41/10-1/10)%%1 (PR#13863)
Not a bug, just a FAQ (7.31). http://CRAN.R-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f On Sat, 1 Aug 2009, jan.hattend...@unibas.ch wrote: Full_Name: jan hattendorf Version: 2.9.0 OS: XP Submission from: (NULL) (213.3.108.185) I get an incorrect result for (41/10-1/10)%%1 [1] 1 The error did not occur with other numbers than 41 (1, 11, 21, 31, 51, ...) test <- rep(NA, 1000) for(i in 1:1000){ test[i] <- i/10-1/10 } test[test%%1==0] __ 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
Re: [Rd] incorrect result (41/10-1/10)%%1 (PR#13863)
jan.hattend...@unibas.ch wrote: > Full_Name: jan hattendorf > Version: 2.9.0 > OS: XP > Submission from: (NULL) (213.3.108.185) > > > I get an incorrect result for > > (41/10-1/10)%%1 > > [1] 1 > > The error did not occur with other numbers than 41 (1, 11, 21, 31, 51, ...) > > > test <- rep(NA, 1000) > for(i in 1:1000){ > test[i] <- i/10-1/10 > } > test[test%%1==0] > > __ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel FAQ 7.31 -- O__ Peter Dalgaard Øster Farimagsgade 5, Entr.B c/ /'_ --- Dept. of Biostatistics PO Box 2099, 1014 Cph. K (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~ - (p.dalga...@biostat.ku.dk) FAX: (+45) 35327907 __ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
[Rd] incorrect result (41/10-1/10)%%1 (PR#13863)
Full_Name: jan hattendorf Version: 2.9.0 OS: XP Submission from: (NULL) (213.3.108.185) I get an incorrect result for (41/10-1/10)%%1 [1] 1 The error did not occur with other numbers than 41 (1, 11, 21, 31, 51, ...) test <- rep(NA, 1000) for(i in 1:1000){ test[i] <- i/10-1/10 } test[test%%1==0] __ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel