增加分段回归

src/main/java/org/wlld/regressionForest/Forest.java

@@ -18,8 +18,6 @@ public class Forest extends Frequency {
     private Forest forestLeft;//左森林
     private Forest forestRight;//右森林
     private int featureSize;
-    private double min;//下限
-    private double max;//上限
     private double resultVariance;//结果矩阵方差
     private double median;//结果矩阵中位数
     private double shrinkParameter;//方差收缩参数
@@ -31,6 +29,10 @@ public class Forest extends Frequency {
         w = new double[featureSize];
     }
 
+    public double getMedian() {
+        return median;
+    }
+
     public double getResultVariance() {
         return resultVariance;
     }
@@ -85,36 +87,14 @@ public class Forest extends Frequency {
             double leftVar = variance(resultLeft);
             double rightVar = variance(resultRight);
             double variance = resultVariance * shrinkParameter;
-            if (leftVar < variance || rightVar < variance) {//继续拆分
-                double[] left = getLimit(resultLeft);
-                double[] right = getLimit(resultRight);
-                forestLeft.setMin(left[0]);
-                forestLeft.setMax(left[1]);
-                forestRight.setMin(right[0]);
-                forestRight.setMax(right[1]);
-            } else {//不继续拆分
+            if (leftVar > variance && rightVar > variance) {//不进行拆分，回退
                 forestLeft = null;
                 forestRight = null;
+                median = 0;
             }
         }
     }
 
-    public double getMin() {
-        return min;
-    }
-
-    public void setMin(double min) {
-        this.min = min;
-    }
-
-    public double getMax() {
-        return max;
-    }
-
-    public void setMax(double max) {
-        this.max = max;
-    }
-
     public Matrix getConditionMatrix() {
         return conditionMatrix;
     }

src/main/java/org/wlld/regressionForest/RegressionForest.java

@@ -24,7 +24,7 @@ public class RegressionForest extends Frequency {
     public RegressionForest(int size, int featureNub) throws Exception {//初始化
         if (size > 0 && featureNub > 0) {
             this.featureNub = featureNub;
-            w = new double[size];
+            w = new double[featureNub];
             results = new double[size];
             conditionMatrix = new Matrix(size, featureNub);
             resultMatrix = new Matrix(size, 1);
@@ -37,8 +37,56 @@ public class RegressionForest extends Frequency {
         }
     }
 
-    public void getDist(double[] feature, double result) {//获取特征误差结果
+    public double getDist(double[] feature, double result) {//获取特征误差结果
+        Forest forestFinish;
+        if (result <= min) {//直接找下边界区域
+            forestFinish = getLimitRegion(forest, false);
+        } else if (result >= max) {//直接找到上边界区域
+            forestFinish = getLimitRegion(forest, true);
+        } else {
+            forestFinish = getRegion(forest, result);
+        }
+        //计算误差
+        double[] w = forestFinish.getW();
+        double sigma = 0;
+        for (int i = 0; i < w.length; i++) {
+            double nub;
+            if (i < w.length - 1) {
+                nub = w[i] * feature[i];
+            } else {
+                nub = w[i];
+            }
+            sigma = sigma + nub;
+        }
+        return Math.abs(result - sigma);
+    }
 
+    private Forest getRegion(Forest forest, double result) {
+        double median = forest.getMedian();
+        if (median > 0) {//进行了拆分
+            if (result > median) {//向右走
+                forest = forest.getForestRight();
+            } else {//向左走
+                forest = forest.getForestLeft();
+            }
+            return getRegion(forest, result);
+        } else {//没有拆分
+            return forest;
+        }
+    }
+
+    private Forest getLimitRegion(Forest forest, boolean isMax) {
+        Forest forestSon;
+        if (isMax) {
+            forestSon = forest.getForestRight();
+        } else {
+            forestSon = forest.getForestLeft();
+        }
+        if (forestSon != null) {
+            return getLimitRegion(forestSon, isMax);
+        } else {
+            return forest;
+        }
     }
 
     public void insertFeature(double[] feature, double result) throws Exception {//插入数据
@@ -99,7 +147,7 @@ public class RegressionForest extends Frequency {
 
     }
 
-    private void regression(Forest forest) throws Exception {
+    private void regression(Forest forest) throws Exception {//对分段进行线性回归
         Matrix conditionMatrix = forest.getConditionMatrix();
         Matrix resultMatrix = forest.getResultMatrix();
         double[] w = forest.getW();