It has changed it, there's now a mix of POLYGON and MULTIPOLYGON geometries, but no change in the underlying coordinates. You have to use the dTolerance argument:
nrow(st_coordinates(nc)) [1] 2529 nrow(st_coordinates(st_cast(nc_simplfy))) [1] 2529 nrow(st_coordinates(st_cast(st_simplify(nc, dTolerance = 1000)))) [1] 1941 It still might change the geometry with dTolerance = 0 (the default), in that case it will remove vertices that are collinear (unnecessarily dense straight lines, reduce to two-vertex edges). I only learnt that recently. HTH On Mon, Jul 22, 2019 at 8:15 PM Hugo Costa <hugoagco...@gmail.com> wrote: > Dear list, > > function st_simplify outputs exactly the same geometry as the input. This > is an example: > > library(sf) > > nc = st_read(system.file("shape/nc.shp", package="sf")) > nc <- nc %>% st_transform(3857) > plot(st_geometry(nc)) > > nc_simplfy<-st_simplify(nc) > plot(st_geometry(nc_simplfy)) > > However, I'm quite sure some days ago st_simpliffy was working as expected. > Could it be something wrong in my machine? What am I missing? > > > sessionInfo() > R version 3.5.3 (2019-03-11) > Platform: x86_64-w64-mingw32/x64 (64-bit) > Running under: Windows >= 8 x64 (build 9200) > > Matrix products: default > > locale: > [1] LC_COLLATE=Portuguese_Portugal.1252 LC_CTYPE=Portuguese_Portugal.1252 > LC_MONETARY=Portuguese_Portugal.1252 LC_NUMERIC=C > [5] LC_TIME=Portuguese_Portugal.1252 > > attached base packages: > [1] stats graphics grDevices utils datasets methods base > > other attached packages: > [1] sf_0.7-3 > > loaded via a namespace (and not attached): > [1] compiler_3.5.3 magrittr_1.5 class_7.3-15 DBI_1.0.0 > tools_3.5.3 units_0.6-2 Rcpp_1.0.1 grid_3.5.3 e1071_1.7-0.1 > [10] classInt_0.3-1 > > [[alternative HTML version deleted]] > > _______________________________________________ > R-sig-Geo mailing list > R-sig-Geo@r-project.org > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > -- Michael Sumner Software and Database Engineer Australian Antarctic Division Hobart, Australia e-mail: mdsum...@gmail.com [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo