fixes for getSubset() (#1979)

core/src/processing/data/FloatList.java

@@ -577,17 +577,18 @@ public class FloatList implements Iterable<Float> {
 //  }
 
 
-  public void subset(int start) {
-    subset(start, count - start);
-  }
+//  public void subset(int start) {
+//    subset(start, count - start);
+//  }
 
 
-  public void subset(int start, int num) {
-    for (int i = 0; i < num; i++) {
-      data[i] = data[i+start];
-    }
-    count = num;
-  }
+//  public void subset(int start, int num) {
+//    for (int i = 0; i < num; i++) {
+//      data[i] = data[i+start];
+//    }
+//    count = num;
+//  }
+
 
   /**
    * @webref floatlist:method
@@ -707,6 +708,18 @@ public class FloatList implements Iterable<Float> {
   }
 
 
+  public FloatList getSubset(int start) {
+    return getSubset(start, count - start);
+  }
+
+
+  public FloatList getSubset(int start, int num) {
+    float[] subset = new float[num];
+    System.arraycopy(data, start, subset, 0, num);
+    return new FloatList(subset);
+  }
+
+
   @Override
   public String toString() {
     StringBuilder sb = new StringBuilder();

core/src/processing/data/IntList.java

@@ -704,11 +704,9 @@ public class IntList implements Iterable<Integer> {
 
 
   public IntList getSubset(int start, int num) {
-    IntList outgoing = new IntList(num);
-    for (int i = 0; i < num; i++) {
-      System.arraycopy(data, start, outgoing.data, 0, num);
-    }
-    return outgoing;
+    int[] subset = new int[num];
+    System.arraycopy(data, start, subset, 0, num);
+    return new IntList(subset);
   }
 
 

core/src/processing/data/StringList.java

@@ -648,11 +648,9 @@ public class StringList implements Iterable<String> {
 
 
   public StringList getSubset(int start, int num) {
-    StringList outgoing = new StringList(num);
-    for (int i = 0; i < num; i++) {
-      System.arraycopy(data, start, outgoing.data, 0, num);
-    }
-    return outgoing;
+    String[] subset = new String[num];
+    System.arraycopy(data, start, subset, 0, num);
+    return new StringList(subset);
   }