io.clj

;;
;; Storing and reading data from different formats
;; @author Antonio Garrote
;;

(ns #^{:author "Antonio Garrote <antoniogarrote@gmail.com>"}
  clj-ml.io
  "Functions for reading and saving datasets, classifiers and clusterers to files and other
   persistence mechanisms."
  (:import (weka.core.converters CSVLoader ArffLoader XRFFLoader LibSVMLoader)
           (weka.core.converters CSVSaver ArffSaver XRFFSaver LibSVMSaver)
           (java.io File InputStream OutputStream)
           (java.net URL URI))
  (:use [clojure.java.io :only [input-stream output-stream]]))


;; Loading of instances

(defmulti load-instances
  "Load instances from different data sources"
  (fn [kind source & options] kind))

(defmacro m-load-instances [loader source]
  `(do
     (if (= (class ~source) java.io.File)
       (.setFile ~loader ~source)
       (.setSource ~loader (if (= (class ~source) java.lang.String)
                             (input-stream ~source)
                             ^InputStream ~source)))
     (.getDataSet ~loader)))

(defmethod load-instances :arff
  ([kind source & options]
     (let [loader (new ArffLoader)]
       (m-load-instances loader source))))


(defmethod load-instances :xrff
  ([kind source & options]
     (let [loader (new XRFFLoader)]
       (m-load-instances loader source))))

(defmethod load-instances :csv
  ([kind source & options]
     (let [loader (new CSVLoader)]
       (m-load-instances loader source))))

(defmethod load-instances :libsvm
  ([kind source & options]
     (let [loader (new LibSVMLoader)]
       (m-load-instances loader source))))

;; Saving of instances

(defmulti save-instances
  "Save instances into data destinies"
  (fn [kind destiny instances & options] kind))

(defmacro m-save-instances [saver destiny instances]
  `(do
     (condp #(isa? %2 %1) (class ~destiny)
       String (.setDestination ~saver (output-stream ~destiny))
       File (.setFile ~saver ~destiny)
       OutputStream (.setDestination ~saver ~destiny))
     (.setInstances ~saver ~instances)
     (.writeBatch ~saver)))

(defmethod save-instances :arff
  ([kind destiny instances & options]
     (let [saver (new ArffSaver)]
       (m-save-instances saver destiny instances))))

(defmethod save-instances :xrff
  ([kind destiny instances & options]
     (let [saver (new XRFFSaver)]
       (m-save-instances saver destiny instances))))

(defmethod save-instances :csv
  ([kind destiny instances & options]
     (let [saver (new CSVSaver)]
       (m-save-instances saver destiny instances))))

(defmethod save-instances :libsvm
  ([kind destiny instances & options]
     (let [saver (new LibSVMSaver)]
       (m-save-instances saver destiny instances))))