Passing vectors into R

In order to do very complex or meaningful analysis, we'll need to be able to pass vector or matrix data into R to operate on and analyze.

Let's see how to do this.

Getting ready

We must first complete the recipe, Setting up R to talk to Clojure, and have Rserve running. We must also have the Clojure-specific parts of that recipe done and the connection to Rserve made.

We'll also need access to the clojure.string namespace:

(require '[clojure.string :as str])

How to do it…

To make passing values into R easier, we'll first define a protocol and then we'll use it to pass a matrix to R:

1. In order to handle the conversion of all the data types into a string that R can read, we'll define a protocol, ToR. Any data types that we want to marshal into R must implement this, as follows:

   (defprotocol ToR
     (->r [x] "Convert an item to R."))

2. Now we'll implement this protocol for sequences, vectors, and numeric types:

   (extend-protocol ToR
     clojure.lang.ISeq
     (->r [coll] (str "c(" (str...