identical(coordinates)
Dear all, I need to convert several times sp objects from data.frame and use zerodist2() to match locations. As zerodist2() seems to use identical(), something seems strange to me: library(sp) xy <- data.frame(x=rnorm(4), y=rnorm(4)) dfxy <- xy coordinates(xy) <- ~ x + y dfxy[1,1] coordinates(xy)[1,1] identical(dfxy[1,1], coordinates(xy)[1,1]) > FALSE # I should expect TRUE!? coordinates(dfxy) <- ~ x + y identical(coordinates(dfxy)[1,1], coordinates(xy)[1,1]) > TRUE Why identical(dfxy[1,1], coordinates(xy)[1,1]) gives FALSE? Thanks, David sessionInfo() R version 2.14.1 (2011-12-22) Platform: i386-pc-mingw32/i386 (32-bit) locale: [1] LC_COLLATE=French_France.1252 LC_CTYPE=French_France.1252 LC_MONETARY=French_France.1252 LC_NUMERIC=C [5] LC_TIME=French_France.1252 attached base packages: [1] stats graphics grDevices utils datasets methods base other attached packages: [1] rgdal_0.7-5 trip_1.1-10 maptools_0.8-12 lattice_0.20-0 foreign_0.8-48 rgeos_0.1-17 stringr_0.6 [8] sp_0.9-93 spatstat_1.25-1 deldir_0.0-16 mgcv_1.7-12 loaded via a namespace (and not attached): [1] grid_2.14.1 Matrix_1.0-2 nlme_3.1-102 plyr_1.7.1 tools_2.14.1
*************************************************** Dr. David PINAUD Ing?nieur de Recherche "Analyses spatiales" Centre d'Etudes Biologiques de Chiz? - CNRS UPR1934 79360 Villiers-en-Bois, France poste 485 Tel: +33 (0)5.49.09.35.58 Fax: +33 (0)5.49.09.65.26 http://www.cebc.cnrs.fr/ *************************************************** -------------- next part -------------- A non-text attachment was scrubbed... Name: pinaud.vcf Type: text/x-vcard Size: 324 bytes Desc: not available URL: <https://stat.ethz.ch/pipermail/r-sig-geo/attachments/20120210/366833d1/attachment.vcf>