Javadoc updates

Author: Lee Rhodes

src/main/java/com/yahoo/sketches/quantiles/HeapUnion.java

@@ -100,7 +100,7 @@ static HeapQuantilesSketch unionUpdateLogic(HeapQuantilesSketch qs1, HeapQuantil
       return qs1;
     }
 
-    //myK > thatK
+    //qs1K > qs2K
     HeapQuantilesSketch copyQS2 = HeapQuantilesSketch.copy(qs2);
     HeapUnion.mergeInto(qs1, copyQS2);
     return copyQS2;

src/main/java/com/yahoo/sketches/quantiles/QuantilesSketch.java

@@ -315,31 +315,6 @@ public String toString() {
    */
   public abstract String toString(boolean sketchSummary, boolean dataDetail);
 
-  //Merging etc
-  
-//  /**
-//   * Merges the given sketch into this one.
-//   * Merges the source sketch into this sketch that can have a smaller value of K.
-//   * However, it is required that the ratio of the two K values be a power of 2.
-//   * I.e., source.getK() = this.getK() * 2^(nonnegative integer). 
-//   * The source is not modified.
-//   *
-//   * @param source the given source sketch
-//   */
-//  public void merge(QuantilesSketch source) {
-//    mergeInto(source, this);
-//  }
-//  
-//  /**
-//   * Merges the source sketch into the target sketch that can have a smaller value of K.
-//   * However, it is required that the ratio of the two K values be a power of 2.
-//   * I.e., source.getK() = target.getK() * 2^(nonnegative integer).
-//   * The source is not modified.
-//   * 
-//   * @param source The source sketch
-//   * @param target The target sketch
-//   */
-//   public abstract void mergeInto(QuantilesSketch source, QuantilesSketch target);
 
    /**
     * From an existing sketch, this creates a new sketch that can have a smaller value of K.

src/main/java/com/yahoo/sketches/quantiles/Union.java

@@ -65,12 +65,22 @@ public static final UnionBuilder builder() {
   public abstract QuantilesSketch getResult();
 
   /**
-   * Resets this Union to its virgin state.
+   * Resets this Union to a virgin state.
    */
   public abstract void reset();
 
+  /**
+   * Returns summary information about the backing sketch.
+   */
   @Override
   public abstract String toString();
 
+  
+  /**
+   * Returns summary information about the backing sketch. Used for debugging.
+   * @param sketchSummary if true includes sketch summary
+   * @param dataDetail if true includes data detail
+   * @return summary information about the sketch.
+   */
   public abstract String toString(boolean sketchSummary, boolean dataDetail);
 }