Creating polygons from sparse data in R-CodePudding

I have a dataframe with coordinates for which I want to create polygons, the most normal is a polygon like the one I put in the first image:

But I'm looking for something different, more like this:

As you can see, if the points are enough far, another polygon is created, is this possible in R? Thanks!

Here are the data csv

CodePudding user response：

I think you would find the concept of concave/alpha hulls relevant. There's an R package alphahull that may cover your need.

install.packages("alphahull")
library(alphahull)
fff <- readr::read_csv("data.csv")
dddd <- ahull(fff[,2:3],alpha = 0.01)
plot(dddd)

And in case you need to convert this output into a spatial data format, please see the following: https://babichmorrowc.github.io/post/2019-03-18-alpha-hull/