support for multidimensional points for shingled forests

src/main/java/rrcf/general/MultiShingledForest.java

@@ -0,0 +1,77 @@
+package rrcf.general;
+
+import java.util.Deque;
+import java.util.ArrayDeque;
+import java.util.Random;
+import java.io.Serializable;
+
+/**
+ * Represents a forest with support for shingling
+ * now working also with multidimensional points
+ */
+public class MultiShingledForest extends Forest implements Serializable {
+	  private int shingleSize;
+    private Deque<Double[]> buffer;
+
+    public MultiShingledForest(Random random, int shingleSize, int numTrees, int treeSize, double[][] data) {
+        super(random, numTrees, treeSize, shinglePoints(shingleSize, data));
+        this.shingleSize = shingleSize;
+        buffer = new ArrayDeque<>();
+        for (int i = 0; i < shingleSize; i++) {
+            int d = data.length - 1 - i;
+            if (d < 0) {
+                break;
+            }
+
+            buffer.addFirst(doubleToDouble(data[d]));
+        }
+    }
+
+    public MultiShingledForest(Random random, int shingleSize, int numTrees, int treeSize) {
+        this(random, shingleSize, numTrees, treeSize, new double[0][0]);
+    }
+
+    public MultiShingledForest(int shingleSize, int numTrees, int treeSize) {
+        this(new Random(), shingleSize, numTrees, treeSize);
+    }
+
+    private static double[][] shinglePoints(int shingleSize, double[][] data) {
+        if (data.length < shingleSize) {
+            return new double[0][shingleSize];
+        }
+        double[][] shingled = new double[data.length - shingleSize + 1][shingleSize];
+        for (int i = 0; i < data.length - shingleSize + 1; i++) {
+            System.arraycopy(data, i, shingled[i], 0, shingleSize);
+        }
+        return shingled;
+    }
+
+    private double[] unboxArray(Double[][] arr) {
+        double[] output = new double[arr.length*arr[0].length];
+        for (int i = 0; i < arr.length; i++) 
+        	for (int j = 0; j < arr[0].length; j++) 
+        		output[i*arr[0].length + j] = arr[i][j];
+        return output;
+    }
+
+    @Override
+    public double addPoint(double[] value) {
+    	buffer.addLast(doubleToDouble(value));
+        if (buffer.size() < shingleSize) {
+            return 0;
+        } else {
+            if (buffer.size() > shingleSize) {
+                buffer.removeFirst();
+            }
+            return super.addPoint(unboxArray(buffer.toArray(new Double[buffer.size()][value.length])));
+        }
+    }
+
+    //TODO import org.apache.commons.lang3.ArrayUtils;
+    public Double[] doubleToDouble(double[] d) {
+    	Double[] n = new Double[d.length];
+    	for (int i = 0; i < d.length; i++)
+			n[i] = d[i];
+    	return n;
+    }
+}