src/test/java/org/apache/datasketches/quantilescommon/PartitionBoundariesTest.java - datasketches-java - Git at Google

 /*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
  * regarding copyright ownership.  The ASF licenses this file
  * to you under the Apache License, Version 2.0 (the
  * "License"); you may not use this file except in compliance
  * with the License.  You may obtain a copy of the License at
  *
  *   http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing,
  * software distributed under the License is distributed on an
  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  * KIND, either express or implied.  See the License for the
  * specific language governing permissions and limitations
  * under the License.
  */

 package org.apache.datasketches.quantilescommon;

 import static org.apache.datasketches.common.Util.LS;
 import static org.apache.datasketches.quantilescommon.LongsAsOrderableStrings.digits;
 import static org.apache.datasketches.quantilescommon.LongsAsOrderableStrings.getString;
 import static org.apache.datasketches.quantilescommon.QuantileSearchCriteria.EXCLUSIVE;
 import static org.apache.datasketches.quantilescommon.QuantileSearchCriteria.INCLUSIVE;
 import static org.testng.Assert.assertEquals;
 import static org.testng.Assert.fail;

 import java.util.Comparator;

 import org.apache.datasketches.common.ArrayOfStringsSerDe;
 import org.apache.datasketches.common.SketchesArgumentException;
 import org.apache.datasketches.kll.KllItemsSketch;
 import org.apache.datasketches.quantiles.ItemsSketch;
 import org.testng.annotations.Test;

 /**
  * This tests partition boundaries with both KllItemsSketch and classic ItemsSketch
  */
 public class PartitionBoundariesTest {
   private ArrayOfStringsSerDe serDe = new ArrayOfStringsSerDe();
   private static String[] hdr     = {"N", "MaxItem", "MinItem", "NumParts", "SearchCriteria"};
   private static String hdrfmt    = "%6s %10s %10s %10s %15s" + LS;
   private static String hdrdfmt   = "%6d %10s %10s %10d %15s" + LS;

   private static String[] rowhdr  = {"Row", "NormRanks", "NatRanks", "Boundaries", "DeltaItems"};
   private static String rowhdrfmt = "%5s %12s %12s %12s %12s" + LS;
   private static String rowdfmt   = "%5d %12.8f %12d %12s %12d" + LS;

   private static String[] rowhdr2 = {"Row", "NormRanks", "NatRanks", "Boundaries"};
   private static String rowhdrfmt2= "%5s %12s %12s %12s" + LS;
   private static String rowdfmt2  = "%5d %12.8f %12d %12s" + LS;

   //@Test //visual check only. set enablePrinting = true to view.
   public void checkSkewWithClassic() {
     int n = 2050; //1000000;
     int k = 1 << 15;
     int n2 = 200;
     int totalN = n + n2;
     int numDigits = digits(totalN);
     long v2 = 1000L;
     QuantileSearchCriteria searchCrit = QuantileSearchCriteria.INCLUSIVE;
     ItemsSketch<String> sk = ItemsSketch.getInstance(String.class,k, Comparator.naturalOrder());

     for (long i = 1; i <= n; i++)  { sk.update(getString(i, numDigits)); }
     for (long i = 1; i <= n2; i++) { sk.update(getString(v2, numDigits)); }
     int numParts = sk.getMaxPartitions(); //22
     ItemsSketchSortedView<String> sv = sk.getSortedView();
     GenericSortedViewIterator<String> itr = sv.iterator();
     println("SORTED VIEW:");
     printf(rowhdrfmt2, (Object[])rowhdr2);
     int j = 0;
     while (itr.next()) {
       printf(rowdfmt2, j++, itr.getNormalizedRank(searchCrit), itr.getNaturalRank(searchCrit), itr.getQuantile());
     }

     GenericPartitionBoundaries<String> gpb = sv.getPartitionBoundariesFromNumParts(numParts, searchCrit);
     int arrLen = gpb.getBoundaries().length;
     double[] normRanks = gpb.getNormalizedRanks();
     long[] natRanks = gpb.getNaturalRanks();
     String[] boundaries = gpb.getBoundaries();
     long[] numDeltaItems = gpb.getNumDeltaItems();
     println("");
     println("GET PARTITION BOUNDARIES:");
     printf(hdrfmt, (Object[]) hdr);
     printf(hdrdfmt, totalN, gpb.getMaxItem(), gpb.getMinItem(), numParts, searchCrit.toString());
     println("");
     printf(rowhdrfmt, (Object[]) rowhdr);
     for (int i = 0; i < arrLen; i++) {
       printf(rowdfmt, i, normRanks[i], natRanks[i], boundaries[i], numDeltaItems[i]);
     }
   }

   //@Test //visual check only. set enablePrinting = true to view.
   public void checkSkewWithKll() {
     int n = 2050; //1_000_000;
     int k = 1 << 15;
     int n2 = 200;
     int totalN = n + n2;
     int numDigits = digits(totalN);
     long v2 = 1000L;
     QuantileSearchCriteria searchCrit = QuantileSearchCriteria.INCLUSIVE;
     KllItemsSketch<String> sk = KllItemsSketch.newHeapInstance(k, Comparator.naturalOrder(), serDe);

     for (long i = 1; i <= n; i++)  { sk.update(getString(i, numDigits)); }
     for (long i = 1; i <= n2; i++) { sk.update(getString(v2, numDigits)); }
     int numParts = sk.getMaxPartitions(); //22
     ItemsSketchSortedView<String> sv = sk.getSortedView();
     GenericSortedViewIterator<String> itr = sv.iterator();
     println("SORTED VIEW:");
     printf(rowhdrfmt2, (Object[])rowhdr2);
     int j = 0;
     while (itr.next()) {
       printf(rowdfmt2, j++, itr.getNormalizedRank(searchCrit), itr.getNaturalRank(searchCrit), itr.getQuantile());
     }

     GenericPartitionBoundaries<String> gpb = sv.getPartitionBoundariesFromNumParts(numParts, searchCrit);
     int arrLen = gpb.getBoundaries().length;
     double[] normRanks = gpb.getNormalizedRanks();
     long[] natRanks = gpb.getNaturalRanks();
     String[] boundaries = gpb.getBoundaries();
     long[] numDeltaItems = gpb.getNumDeltaItems();
     println("");
     println("GET PARTITION BOUNDARIES:");
     printf(hdrfmt, (Object[]) hdr);
     printf(hdrdfmt, totalN, gpb.getMaxItem(), gpb.getMinItem(), numParts, searchCrit.toString());
     println("");
     printf(rowhdrfmt, (Object[]) rowhdr);
     for (int i = 0; i < arrLen; i++) {
       printf(rowdfmt, i, normRanks[i], natRanks[i], boundaries[i], numDeltaItems[i]);
     }
   }

   @Test
   public void getQuantilesVsPartitionBoundariesKll() {
     final KllItemsSketch<String> sketch = KllItemsSketch.newHeapInstance(Comparator.naturalOrder(), serDe);
     sketch.update("A");
     sketch.update("B");
     sketch.update("C");
     sketch.update("D");
     String[] quantiles1 = sketch.getQuantiles(new double[] {0.0, 0.5, 1.0}, EXCLUSIVE);
     String[] quantiles2 = sketch.getPartitionBoundariesFromNumParts(2, EXCLUSIVE).getBoundaries();
     assertEquals(quantiles1, quantiles2);
     quantiles1 = sketch.getQuantiles(new double[] {0.0, 0.5, 1.0}, INCLUSIVE);
     quantiles2 = sketch.getPartitionBoundariesFromNumParts(2, INCLUSIVE).getBoundaries();
     assertEquals(quantiles1, quantiles2);
   }

   @Test
   public void getQuantilesVsPartitionBoundariesClassic() {
     final ItemsSketch<Integer> sketch = ItemsSketch.getInstance(Integer.class, Comparator.naturalOrder());
     sketch.update(1);
     sketch.update(2);
     sketch.update(3);
     sketch.update(4);
     Integer[] quantiles1 = sketch.getQuantiles(new double[] {0.0, 0.5, 1.0}, EXCLUSIVE);
     Integer[] quantiles2 = sketch.getPartitionBoundariesFromNumParts(2, EXCLUSIVE).getBoundaries();
     assertEquals(quantiles1, quantiles2);
     quantiles1 = sketch.getQuantiles(new double[] {0.0, 0.5, 1.0}, INCLUSIVE);
     quantiles2 = sketch.getPartitionBoundariesFromNumParts(2, INCLUSIVE).getBoundaries();
     assertEquals(quantiles1, quantiles2);
   }

   /**
    * Because both Kll and Classic items sketches use the same Sorted View class.
    * This test applies to both.
    */
   @Test
   public void checkSimpleEndsAdjustment() {
     final String[] quantiles = {"2","4","6","7"};
     final long[] cumWeights = {2, 4, 6, 8};
     final long totalN = 8;
     final Comparator<String> comparator = Comparator.naturalOrder();
     final String maxItem = "8";
     final String minItem = "1";
     ItemsSketchSortedView<String> sv = new ItemsSketchSortedView<>(
         quantiles, cumWeights, totalN, comparator, maxItem, minItem,
         String.class, .01, 4);

     GenericSortedViewIterator<String> itr = sv.iterator();
     while (itr.next()) {
       println(itr.getNaturalRank(INCLUSIVE) + ", " + itr.getQuantile(INCLUSIVE));
     }
     GenericPartitionBoundaries<String> gpb = sv.getPartitionBoundariesFromNumParts(2);
     String[] boundaries = gpb.getBoundaries();
     long[] natRanks = gpb.getNaturalRanks();
     double[] normRanks = gpb.getNormalizedRanks();
     long[] deltaItems = gpb.getNumDeltaItems();
     int numParts = gpb.getNumPartitions();
     String maxItm = gpb.getMaxItem();
     String minItm = gpb.getMinItem();
     assertEquals(boundaries, new String[] {"1","4","8"});
     assertEquals(natRanks, new long[] {1,4,8});
     assertEquals(normRanks, new double[] {.125,.5,1.0});
     assertEquals(deltaItems, new long[] {0,4,4});
     assertEquals(numParts, 2);
     assertEquals(maxItm, "8");
     assertEquals(minItm, "1");
   }

   @SuppressWarnings("unused")
   @Test //For visual check, set enablePrinting = true to view.
   public void checkSketchPartitionLimits() {
     final long totalN = 2000; //1_000_000;
     final Comparator<String> comparator = Comparator.naturalOrder();
     final ArrayOfStringsSerDe serDe = new ArrayOfStringsSerDe();
     final int k = 1 << 15;
     final KllItemsSketch<String> sk = KllItemsSketch.newHeapInstance(k, comparator, serDe);
     final int d = digits(totalN);
     for (int i = 1; i <= totalN; i++) {
       sk.update(getString(i, d));
     }
     //***
     final int numRet = sk.getNumRetained();
     println("NumRetained: " + numRet + " /2: " + (numRet / 2));
     final double eps = sk.getNormalizedRankError(true);
     printf("NormRankErr: %10.6f     1/eps: %10.3f" + LS, eps, 1/eps);
     //***
     //this should pass
     final int goodNumPartsRequest = sk.getMaxPartitions();
     println("Good numPartsRequest " + goodNumPartsRequest);
     GenericPartitionBoundaries<String> gpb = sk.getPartitionBoundariesFromNumParts(goodNumPartsRequest);
     //this should fail
     try {
       final int badNumPartsRequest = goodNumPartsRequest + 1;
       println("Bad numPartsRequest " + badNumPartsRequest);
       gpb = sk.getPartitionBoundariesFromNumParts(badNumPartsRequest);
       fail("Bad numPartsRequest should have failed. " + badNumPartsRequest);
     } catch (SketchesArgumentException e) { } //OK
   }

   @SuppressWarnings("unused")
   @Test //For visual check, set enablePrinting = true to view.
   public void checkSketchPartitionLimits2() {
     final long totalN = 2000; //1_000_000;
     final Comparator<String> comparator = Comparator.naturalOrder();
     final ArrayOfStringsSerDe serDe = new ArrayOfStringsSerDe();
     final int k = 1 << 15;
     final KllItemsSketch<String> sk = KllItemsSketch.newHeapInstance(k, comparator, serDe);
     final int d = digits(totalN);
     for (int i = 1; i <= totalN; i++) {
       sk.update(getString(i, d));
     }
     final double eps = sk.getNormalizedRankError(true);
     printf("NormRankErr: %10.6f     1/eps: %10.3f" + LS, eps, 1/eps);
     println("N: " + sk.getN());
     println("Max Parts: " + sk.getMaxPartitions());

     //this should pass
     final long goodPartSizeRequest= sk.getMinPartitionSizeItems();
     println("Good partSizeRequest " + goodPartSizeRequest);
     GenericPartitionBoundaries<String> gpb = sk.getPartitionBoundariesFromPartSize(goodPartSizeRequest);
     //this should fail
     try {
       final long badPartSizeRequest = goodPartSizeRequest - 1;
       println("Bad partSizeRequest " + badPartSizeRequest);
     } catch (SketchesArgumentException e) { } //OK
   }

   @Test
   public void printlnTest() {
     println("PRINTING: " + this.getClass().getName());
   }

   private final static boolean enablePrinting = false;

   /**
    * @param format the format
    * @param args the args
    */
   static final void printf(final String format, final Object ...args) {
     if (enablePrinting) { System.out.printf(format, args); }
   }

   /**
    * @param o the Object to println
    */
   static final void println(final Object o) {
     if (enablePrinting) { System.out.println(o.toString()); }
   }
 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one
	* or more contributor license agreements. See the NOTICE file
	* distributed with this work for additional information
	* regarding copyright ownership. The ASF licenses this file
	* to you under the Apache License, Version 2.0 (the
	* "License"); you may not use this file except in compliance
	* with the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing,
	* software distributed under the License is distributed on an
	* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	* KIND, either express or implied. See the License for the
	* specific language governing permissions and limitations
	* under the License.
	*/

	package org.apache.datasketches.quantilescommon;

	import static org.apache.datasketches.common.Util.LS;
	import static org.apache.datasketches.quantilescommon.LongsAsOrderableStrings.digits;
	import static org.apache.datasketches.quantilescommon.LongsAsOrderableStrings.getString;
	import static org.apache.datasketches.quantilescommon.QuantileSearchCriteria.EXCLUSIVE;
	import static org.apache.datasketches.quantilescommon.QuantileSearchCriteria.INCLUSIVE;
	import static org.testng.Assert.assertEquals;
	import static org.testng.Assert.fail;

	import java.util.Comparator;

	import org.apache.datasketches.common.ArrayOfStringsSerDe;
	import org.apache.datasketches.common.SketchesArgumentException;
	import org.apache.datasketches.kll.KllItemsSketch;
	import org.apache.datasketches.quantiles.ItemsSketch;
	import org.testng.annotations.Test;

	/**
	* This tests partition boundaries with both KllItemsSketch and classic ItemsSketch
	*/
	public class PartitionBoundariesTest {
	private ArrayOfStringsSerDe serDe = new ArrayOfStringsSerDe();
	private static String[] hdr = {"N", "MaxItem", "MinItem", "NumParts", "SearchCriteria"};
	private static String hdrfmt = "%6s %10s %10s %10s %15s" + LS;
	private static String hdrdfmt = "%6d %10s %10s %10d %15s" + LS;

	private static String[] rowhdr = {"Row", "NormRanks", "NatRanks", "Boundaries", "DeltaItems"};
	private static String rowhdrfmt = "%5s %12s %12s %12s %12s" + LS;
	private static String rowdfmt = "%5d %12.8f %12d %12s %12d" + LS;

	private static String[] rowhdr2 = {"Row", "NormRanks", "NatRanks", "Boundaries"};
	private static String rowhdrfmt2= "%5s %12s %12s %12s" + LS;
	private static String rowdfmt2 = "%5d %12.8f %12d %12s" + LS;

	//@Test //visual check only. set enablePrinting = true to view.
	public void checkSkewWithClassic() {
	int n = 2050; //1000000;
	int k = 1 << 15;
	int n2 = 200;
	int totalN = n + n2;
	int numDigits = digits(totalN);
	long v2 = 1000L;
	QuantileSearchCriteria searchCrit = QuantileSearchCriteria.INCLUSIVE;
	ItemsSketch<String> sk = ItemsSketch.getInstance(String.class,k, Comparator.naturalOrder());

	for (long i = 1; i <= n; i++) { sk.update(getString(i, numDigits)); }
	for (long i = 1; i <= n2; i++) { sk.update(getString(v2, numDigits)); }
	int numParts = sk.getMaxPartitions(); //22
	ItemsSketchSortedView<String> sv = sk.getSortedView();
	GenericSortedViewIterator<String> itr = sv.iterator();
	println("SORTED VIEW:");
	printf(rowhdrfmt2, (Object[])rowhdr2);
	int j = 0;
	while (itr.next()) {
	printf(rowdfmt2, j++, itr.getNormalizedRank(searchCrit), itr.getNaturalRank(searchCrit), itr.getQuantile());
	}

	GenericPartitionBoundaries<String> gpb = sv.getPartitionBoundariesFromNumParts(numParts, searchCrit);
	int arrLen = gpb.getBoundaries().length;
	double[] normRanks = gpb.getNormalizedRanks();
	long[] natRanks = gpb.getNaturalRanks();
	String[] boundaries = gpb.getBoundaries();
	long[] numDeltaItems = gpb.getNumDeltaItems();
	println("");
	println("GET PARTITION BOUNDARIES:");
	printf(hdrfmt, (Object[]) hdr);
	printf(hdrdfmt, totalN, gpb.getMaxItem(), gpb.getMinItem(), numParts, searchCrit.toString());
	println("");
	printf(rowhdrfmt, (Object[]) rowhdr);
	for (int i = 0; i < arrLen; i++) {
	printf(rowdfmt, i, normRanks[i], natRanks[i], boundaries[i], numDeltaItems[i]);
	}
	}

	//@Test //visual check only. set enablePrinting = true to view.
	public void checkSkewWithKll() {
	int n = 2050; //1_000_000;
	int k = 1 << 15;
	int n2 = 200;
	int totalN = n + n2;
	int numDigits = digits(totalN);
	long v2 = 1000L;
	QuantileSearchCriteria searchCrit = QuantileSearchCriteria.INCLUSIVE;
	KllItemsSketch<String> sk = KllItemsSketch.newHeapInstance(k, Comparator.naturalOrder(), serDe);

	for (long i = 1; i <= n; i++) { sk.update(getString(i, numDigits)); }
	for (long i = 1; i <= n2; i++) { sk.update(getString(v2, numDigits)); }
	int numParts = sk.getMaxPartitions(); //22
	ItemsSketchSortedView<String> sv = sk.getSortedView();
	GenericSortedViewIterator<String> itr = sv.iterator();
	println("SORTED VIEW:");
	printf(rowhdrfmt2, (Object[])rowhdr2);
	int j = 0;
	while (itr.next()) {
	printf(rowdfmt2, j++, itr.getNormalizedRank(searchCrit), itr.getNaturalRank(searchCrit), itr.getQuantile());
	}

	GenericPartitionBoundaries<String> gpb = sv.getPartitionBoundariesFromNumParts(numParts, searchCrit);
	int arrLen = gpb.getBoundaries().length;
	double[] normRanks = gpb.getNormalizedRanks();
	long[] natRanks = gpb.getNaturalRanks();
	String[] boundaries = gpb.getBoundaries();
	long[] numDeltaItems = gpb.getNumDeltaItems();
	println("");
	println("GET PARTITION BOUNDARIES:");
	printf(hdrfmt, (Object[]) hdr);
	printf(hdrdfmt, totalN, gpb.getMaxItem(), gpb.getMinItem(), numParts, searchCrit.toString());
	println("");
	printf(rowhdrfmt, (Object[]) rowhdr);
	for (int i = 0; i < arrLen; i++) {
	printf(rowdfmt, i, normRanks[i], natRanks[i], boundaries[i], numDeltaItems[i]);
	}
	}

	@Test
	public void getQuantilesVsPartitionBoundariesKll() {
	final KllItemsSketch<String> sketch = KllItemsSketch.newHeapInstance(Comparator.naturalOrder(), serDe);
	sketch.update("A");
	sketch.update("B");
	sketch.update("C");
	sketch.update("D");
	String[] quantiles1 = sketch.getQuantiles(new double[] {0.0, 0.5, 1.0}, EXCLUSIVE);
	String[] quantiles2 = sketch.getPartitionBoundariesFromNumParts(2, EXCLUSIVE).getBoundaries();
	assertEquals(quantiles1, quantiles2);
	quantiles1 = sketch.getQuantiles(new double[] {0.0, 0.5, 1.0}, INCLUSIVE);
	quantiles2 = sketch.getPartitionBoundariesFromNumParts(2, INCLUSIVE).getBoundaries();
	assertEquals(quantiles1, quantiles2);
	}

	@Test
	public void getQuantilesVsPartitionBoundariesClassic() {
	final ItemsSketch<Integer> sketch = ItemsSketch.getInstance(Integer.class, Comparator.naturalOrder());
	sketch.update(1);
	sketch.update(2);
	sketch.update(3);
	sketch.update(4);
	Integer[] quantiles1 = sketch.getQuantiles(new double[] {0.0, 0.5, 1.0}, EXCLUSIVE);
	Integer[] quantiles2 = sketch.getPartitionBoundariesFromNumParts(2, EXCLUSIVE).getBoundaries();
	assertEquals(quantiles1, quantiles2);
	quantiles1 = sketch.getQuantiles(new double[] {0.0, 0.5, 1.0}, INCLUSIVE);
	quantiles2 = sketch.getPartitionBoundariesFromNumParts(2, INCLUSIVE).getBoundaries();
	assertEquals(quantiles1, quantiles2);
	}

	/**
	* Because both Kll and Classic items sketches use the same Sorted View class.
	* This test applies to both.
	*/
	@Test
	public void checkSimpleEndsAdjustment() {
	final String[] quantiles = {"2","4","6","7"};
	final long[] cumWeights = {2, 4, 6, 8};
	final long totalN = 8;
	final Comparator<String> comparator = Comparator.naturalOrder();
	final String maxItem = "8";
	final String minItem = "1";
	ItemsSketchSortedView<String> sv = new ItemsSketchSortedView<>(
	quantiles, cumWeights, totalN, comparator, maxItem, minItem,
	String.class, .01, 4);

	GenericSortedViewIterator<String> itr = sv.iterator();
	while (itr.next()) {
	println(itr.getNaturalRank(INCLUSIVE) + ", " + itr.getQuantile(INCLUSIVE));
	}
	GenericPartitionBoundaries<String> gpb = sv.getPartitionBoundariesFromNumParts(2);
	String[] boundaries = gpb.getBoundaries();
	long[] natRanks = gpb.getNaturalRanks();
	double[] normRanks = gpb.getNormalizedRanks();
	long[] deltaItems = gpb.getNumDeltaItems();
	int numParts = gpb.getNumPartitions();
	String maxItm = gpb.getMaxItem();
	String minItm = gpb.getMinItem();
	assertEquals(boundaries, new String[] {"1","4","8"});
	assertEquals(natRanks, new long[] {1,4,8});
	assertEquals(normRanks, new double[] {.125,.5,1.0});
	assertEquals(deltaItems, new long[] {0,4,4});
	assertEquals(numParts, 2);
	assertEquals(maxItm, "8");
	assertEquals(minItm, "1");
	}

	@SuppressWarnings("unused")
	@Test //For visual check, set enablePrinting = true to view.
	public void checkSketchPartitionLimits() {
	final long totalN = 2000; //1_000_000;
	final Comparator<String> comparator = Comparator.naturalOrder();
	final ArrayOfStringsSerDe serDe = new ArrayOfStringsSerDe();
	final int k = 1 << 15;
	final KllItemsSketch<String> sk = KllItemsSketch.newHeapInstance(k, comparator, serDe);
	final int d = digits(totalN);
	for (int i = 1; i <= totalN; i++) {
	sk.update(getString(i, d));
	}
	//***
	final int numRet = sk.getNumRetained();
	println("NumRetained: " + numRet + " /2: " + (numRet / 2));
	final double eps = sk.getNormalizedRankError(true);
	printf("NormRankErr: %10.6f 1/eps: %10.3f" + LS, eps, 1/eps);
	//***
	//this should pass
	final int goodNumPartsRequest = sk.getMaxPartitions();
	println("Good numPartsRequest " + goodNumPartsRequest);
	GenericPartitionBoundaries<String> gpb = sk.getPartitionBoundariesFromNumParts(goodNumPartsRequest);
	//this should fail
	try {
	final int badNumPartsRequest = goodNumPartsRequest + 1;
	println("Bad numPartsRequest " + badNumPartsRequest);
	gpb = sk.getPartitionBoundariesFromNumParts(badNumPartsRequest);
	fail("Bad numPartsRequest should have failed. " + badNumPartsRequest);
	} catch (SketchesArgumentException e) { } //OK
	}

	@SuppressWarnings("unused")
	@Test //For visual check, set enablePrinting = true to view.
	public void checkSketchPartitionLimits2() {
	final long totalN = 2000; //1_000_000;
	final Comparator<String> comparator = Comparator.naturalOrder();
	final ArrayOfStringsSerDe serDe = new ArrayOfStringsSerDe();
	final int k = 1 << 15;
	final KllItemsSketch<String> sk = KllItemsSketch.newHeapInstance(k, comparator, serDe);
	final int d = digits(totalN);
	for (int i = 1; i <= totalN; i++) {
	sk.update(getString(i, d));
	}
	final double eps = sk.getNormalizedRankError(true);
	printf("NormRankErr: %10.6f 1/eps: %10.3f" + LS, eps, 1/eps);
	println("N: " + sk.getN());
	println("Max Parts: " + sk.getMaxPartitions());

	//this should pass
	final long goodPartSizeRequest= sk.getMinPartitionSizeItems();
	println("Good partSizeRequest " + goodPartSizeRequest);
	GenericPartitionBoundaries<String> gpb = sk.getPartitionBoundariesFromPartSize(goodPartSizeRequest);
	//this should fail
	try {
	final long badPartSizeRequest = goodPartSizeRequest - 1;
	println("Bad partSizeRequest " + badPartSizeRequest);
	} catch (SketchesArgumentException e) { } //OK
	}

	@Test
	public void printlnTest() {
	println("PRINTING: " + this.getClass().getName());
	}

	private final static boolean enablePrinting = false;

	/**
	* @param format the format
	* @param args the args
	*/
	static final void printf(final String format, final Object ...args) {
	if (enablePrinting) { System.out.printf(format, args); }
	}

	/**
	* @param o the Object to println
	*/
	static final void println(final Object o) {
	if (enablePrinting) { System.out.println(o.toString()); }
	}
	}