docs: Add small docs and remove R install that don't work

pixi.toml

@@ -107,7 +107,3 @@ depends-on = ["install-python"]
 [feature.r.dependencies]
 r = "4.*"
 r-devtools = ">=2.4.5,<3"
-
-[feature.r.tasks.install-r]
-cmd = 'R -e "rextendr::document()"'
-cwd = "r-phylo2vec"

r-phylo2vec/README.md

@@ -0,0 +1,30 @@
+# r-phylo2vec
+
+**NOTE: This is currently in active development and APIs will change. Use at
+your own risk.**
+
+This directory contains the pylo2vec R codebase, which includes Rust binding
+setup.
+
+Open up `R` command line interactive mode within the pixi environment:
+
+```console
+pixi run -e r-phylo2vec R --interactive
+```
+
+Once in R, you can run the following to start using the package:
+
+```R
+# Install rextendr if not already installed
+install.packages("rextendr")
+
+# Install phylo2vec package
+rextendr::document('./r-phylo2vec')
+
+# Import the library
+library('phylo2vec')
+
+# A small demo
+v = sample(5, FALSE)
+to_newick(v)
+```