
R version 3.6.2 (2019-12-12) -- "Dark and Stormy Night"
Copyright (C) 2019 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

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> suppressPackageStartupMessages(library(lwgeom))
> suppressPackageStartupMessages(library(sf))
> nc = st_read(system.file("gpkg/nc.gpkg", package="sf"), quiet = TRUE)
> nc = st_transform(nc, 3857)
> st_perimeter(nc)[1:5]
Units: [m]
[1] 176215.7 149267.4 199588.2 375140.4 263513.1
> st_perimeter_2d(nc)[1:5]
Units: [m]
[1] 176215.7 149267.4 199588.2 375140.4 263513.1
> 
> proc.time()
   user  system elapsed 
  0.395   0.038   0.423 
