cljlab

This library an interface to MATLAB and GNU Octave from within Clojure. This is done by leveraging two existing Java libraries, matlabcontrol and JavaOctave. The point of this library is to smooth over the differences between these two libraries so that you can interface with whichever *lab is available.

A lot of work still needs to be done on ferrying more complex datatypes to/from Clojure. At present, the following work:

• getting and setting flat arrays/lists
• getting and setting 1d strings
• getting matrices of doubles
• getting matrices of strings

So the following don't work:

• setting 2+d matrices
• setting 2+d strings
• structs
• cells

Usage

There are two "levels" to the API. The "basic" level is more or less a straight passthrough to the underlying Java libraries, and as such supports only a limited set of operations (get-basic and set-basic, which operate on flat numeric and string data structures, and eval). Over top of this layer, a set of more sophisticated "higher level" functions is being developed. This layer is incomplete however.

Long-term, the "higher-level" API is expected to grow to include get and set operations on all the core datastructures, as well as a means of easily wrapping functions.

(require '[cljlab :as cl])

(def my-lab (cl/open)) ;; will use either MATLAB or Octave, depending on availability
(cl/type my-lab) ;; returns :matlab or :octave

(def my-ml (cl/open {:type :matlab}))
(def my-oct (cl/open {:type :octave}))

;; "Basic" get
(cl/eval my-lab "x = 1;") ;; => nil
(cl/get-basic my-lab :x) ;; => (1.0); i.e. a list of doubles.
(cl/eval my-lab "x = reshape(1:27, [3 3 3]);") ;; => nil
(cl/get-basic my-lab :x) ;; => (range 1.0 28.0); i.e. flattened

;; "Higher-level" get
(cl/get my-lab :x) ;; =>
                   ;; [[[1.0 10.0 19.0] [4.0 13.0 22.0] [7.0 16.0 25.0]]
                   ;;  [[2.0 11.0 20.0] [5.0 14.0 23.0] [8.0 17.0 26.0]]
                   ;;  [[3.0 12.0 21.0] [6.0 15.0 24.0] [9.0 18.0 27.0]]]

;; "Basic" set
(cl/set-basic my-lab :y (range 0 100 0.5)) ;; => nil; puts a list of doubles into the lab
(cl/get-basic my-lab :y) ;; => (range 0 100 0.5)

(cl/set-basic my-lab :some_str "Testing 1 2 3\n") ;; puts a flat string into some_str in the lab
(cl/eval my-lab "fprintf(some_str);" ;; Won't see anything as stdin/out are not connected up

(cl/open? my-lab) ;; => true

(cl/exit my-lab) ;; Kills the lab

(cl/open? my-lab) ;; => false

(cl/disconnect my-ml) ;; Should leave the lab running after Java exits
(cl/open? my-ml) ;; => false

Output

cljlab can pass the output generated by evaluating functions through to a Writer object (such as *out*) by specifying the writer when constructing the lab instance. For example:

(def lab (cl/open {:type :matlab :out *out*}))
(cl/eval lab "disp('hello');") ;; Should display "hello" followed by a new line

This works for both lab types. Under MATLAB this is achieved using the diary function, so it will break if you run code that alters the diary setting. Also under MATLAB, output will be forwarded to the writer only after each eval call completes.

By default the :out option is set to nil, which means that output will be discarded.

License

cljlab is copyright (C) 2014 Alastair Pharo. Distributed under the Apache License, Version 2.0.