DoublesUtil.java
/*
* 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.quantiles;
import static org.apache.datasketches.common.Util.LS;
import static org.apache.datasketches.quantiles.ClassicUtil.DOUBLES_SER_VER;
import static org.apache.datasketches.quantiles.ClassicUtil.computeCombinedBufferItemCapacity;
import static org.apache.datasketches.quantiles.ClassicUtil.computeNumLevelsNeeded;
import static org.apache.datasketches.quantiles.ClassicUtil.computeTotalLevels;
import static org.apache.datasketches.quantiles.ClassicUtil.computeValidLevels;
import static org.apache.datasketches.quantiles.ClassicUtil.getNormalizedRankError;
import java.util.Arrays;
import org.apache.datasketches.common.SketchesArgumentException;
/**
* Utilities that support the doubles quantiles algorithms.
*
* <p>This class contains a highly specialized sort called blockyTandemMergeSort().
* It also contains methods that are used while building histograms and other common
* functions.</p>
*
* @author Lee Rhodes
*/
final class DoublesUtil {
private DoublesUtil() {}
/**
* Returns an on-heap copy of the given sketch
* @param sketch the given sketch
* @return a copy of the given sketch
*/
static HeapUpdateDoublesSketch copyToHeap(final DoublesSketch sketch) {
final HeapUpdateDoublesSketch qsCopy;
qsCopy = HeapUpdateDoublesSketch.newInstance(sketch.getK());
qsCopy.putN(sketch.getN());
qsCopy.putMinItem(sketch.isEmpty() ? Double.NaN : sketch.getMinItem());
qsCopy.putMaxItem(sketch.isEmpty() ? Double.NaN : sketch.getMaxItem());
qsCopy.putBaseBufferCount(sketch.getBaseBufferCount());
qsCopy.putBitPattern(sketch.getBitPattern());
if (sketch.isCompact()) {
final int combBufItems = computeCombinedBufferItemCapacity(sketch.getK(), sketch.getN());
final double[] combBuf = new double[combBufItems];
qsCopy.putCombinedBuffer(combBuf);
final DoublesSketchAccessor sketchAccessor = DoublesSketchAccessor.wrap(sketch);
final DoublesSketchAccessor copyAccessor = DoublesSketchAccessor.wrap(qsCopy);
// start with BB
copyAccessor.putArray(sketchAccessor.getArray(0, sketchAccessor.numItems()),
0, 0, sketchAccessor.numItems());
long bitPattern = sketch.getBitPattern();
for (int lvl = 0; bitPattern != 0L; ++lvl, bitPattern >>>= 1) {
if ((bitPattern & 1L) > 0L) {
sketchAccessor.setLevel(lvl);
copyAccessor.setLevel(lvl);
copyAccessor.putArray(sketchAccessor.getArray(0, sketchAccessor.numItems()),
0, 0, sketchAccessor.numItems());
}
}
} else {
final double[] combBuf = sketch.getCombinedBuffer();
qsCopy.putCombinedBuffer(Arrays.copyOf(combBuf, combBuf.length));
}
return qsCopy;
}
/**
* Check the validity of the given serialization version
* @param serVer the given serialization version
* @param minSupportedSerVer the oldest serialization version supported
*/
static void checkDoublesSerVer(final int serVer, final int minSupportedSerVer) {
final int max = DOUBLES_SER_VER;
if ((serVer > max) || (serVer < minSupportedSerVer)) {
throw new SketchesArgumentException(
"Possible corruption: Unsupported Serialization Version: " + serVer);
}
}
static String toString(final boolean withLevels, final boolean withLevelsAndItems,
final DoublesSketch sk) {
final StringBuilder sb = new StringBuilder();
sb.append(getSummary(sk));
if (withLevels) {
sb.append(outputLevels(sk));
}
if (withLevelsAndItems) {
sb.append(outputDataDetail(sk));
}
return sb.toString();
}
private static String getSummary(final DoublesSketch sk) {
final StringBuilder sb = new StringBuilder();
final String thisSimpleName = sk.getClass().getSimpleName();
final int k = sk.getK();
final String kStr = String.format("%,d", k);
final long n = sk.getN();
final String nStr = String.format("%,d", n);
final String bbCntStr = String.format("%,d", sk.getBaseBufferCount());
final String combBufCapStr = String.format("%,d", sk.getCombinedBufferItemCapacity());
final long bitPattern = sk.getBitPattern();
final int neededLevels = computeNumLevelsNeeded(k, n);
final int totalLevels = computeTotalLevels(bitPattern);
final int validLevels = computeValidLevels(bitPattern);
final String retItemsStr = String.format("%,d", sk.getNumRetained());
final int preBytes = sk.isEmpty() ? Long.BYTES : 2 * Long.BYTES;
final String cmptBytesStr = String.format("%,d", sk.getCurrentCompactSerializedSizeBytes());
final String updtBytesStr = String.format("%,d", sk.getCurrentUpdatableSerializedSizeBytes());
final double epsPmf = getNormalizedRankError(k, true);
final String epsPmfPctStr = String.format("%.3f%%", epsPmf * 100.0);
final double eps = getNormalizedRankError(k, false);
final String epsPctStr = String.format("%.3f%%", eps * 100.0);
final String memCap = sk.hasMemory() ? Long.toString(sk.getMemory().getCapacity()) : "";
final double minItem = sk.isEmpty() ? Double.NaN : sk.getMinItem();
final double maxItem = sk.isEmpty() ? Double.NaN : sk.getMaxItem();
sb.append(LS).append("### Classic Quantiles ").append(thisSimpleName).append(" SUMMARY: ").append(LS);
sb.append(" Empty : ").append(sk.isEmpty()).append(LS);
sb.append(" Memory, Capacity bytes : ").append(sk.hasMemory()).append(", ").append(memCap).append(LS);
sb.append(" Estimation Mode : ").append(sk.isEstimationMode()).append(LS);
sb.append(" K : ").append(kStr).append(LS);
sb.append(" N : ").append(nStr).append(LS);
sb.append(" Levels (Needed, Total, Valid): ").append(neededLevels + ", " + totalLevels + ", " + validLevels)
.append(LS);
sb.append(" Level Bit Pattern : ").append(Long.toBinaryString(bitPattern)).append(LS);
sb.append(" Base Buffer Count : ").append(bbCntStr).append(LS);
sb.append(" Combined Buffer Capacity : ").append(combBufCapStr).append(LS);
sb.append(" Retained Items : ").append(retItemsStr).append(LS);
sb.append(" Preamble Bytes : ").append(preBytes).append(LS);
sb.append(" Compact Storage Bytes : ").append(cmptBytesStr).append(LS);
sb.append(" Updatable Storage Bytes : ").append(updtBytesStr).append(LS);
sb.append(" Normalized Rank Error : ").append(epsPctStr).append(LS);
sb.append(" Normalized Rank Error (PMF) : ").append(epsPmfPctStr).append(LS);
sb.append(" Min Item : ")
.append(String.format("%12.6e", minItem)).append(LS);
sb.append(" Max Item : ")
.append(String.format("%12.6e", maxItem)).append(LS);
sb.append("### END SKETCH SUMMARY").append(LS);
return sb.toString();
}
private static <T> String outputLevels(final DoublesSketch sk) {
final String name = sk.getClass().getSimpleName();
final int k = sk.getK();
final long n = sk.getN();
final int totNumLevels = computeNumLevelsNeeded(k, n);
final long bitPattern = sk.getBitPattern();
final StringBuilder sb = new StringBuilder();
sb.append(LS).append("### ").append(name).append(" LEVELS ABOVE BASE BUF:").append(LS);
if (totNumLevels == 0) {
sb.append(" <NONE>").append(LS);
} else {
sb.append(" Level | Valid | Weight").append(LS);
for (int i = 0; i < totNumLevels; i++) {
final String wt = "" + (1L << (i + 1));
final String valid = getValidFromLevel(i, bitPattern) ? "T" : "F";
final String row = String.format(" %7s %8s %9s", i, valid, wt);
sb.append(row).append(LS);
}
}
sb.append("### END LEVELS ABOVE BASE BUF").append(LS);
return sb.toString();
}
private static <T> String outputDataDetail(final DoublesSketch sk) {
final String name = sk.getClass().getSimpleName();
final int k = sk.getK();
final long n = sk.getN();
final long bitPattern = sk.getBitPattern();
final int bbCount = sk.getBaseBufferCount();
final int combBufCap = sk.getCombinedBufferItemCapacity();
final StringBuilder sb = new StringBuilder();
sb.append(LS).append("### ").append(name).append(" DATA DETAIL: ").append(LS);
final double[] items = sk.getCombinedBuffer();
if (n == 0) {
sb.append(" <NO DATA>").append(LS);
} else {
sb.append(" Index | Level | Valid | Item").append(LS);
for (int i = 0; i < combBufCap; i++) {
final int levelNum = getLevelNum(k, i);
final String lvlStr = (levelNum == -1) ? "BB" : ("" + levelNum);
final String validLvl = getValidFromIndex(levelNum, bitPattern, i, bbCount) ? "T" : "F";
final String row = String.format("%7s %7s %7s %s", i, lvlStr, validLvl, items[i]);
sb.append(row).append(LS);
}
}
sb.append("### END DATA DETAIL").append(LS);
return sb.toString();
}
private static boolean getValidFromIndex(final int levelNum, final long bitPattern, final int index,
final int bbCount) {
return ((levelNum == -1) && (index < bbCount)) || getValidFromLevel(levelNum, bitPattern);
}
private static boolean getValidFromLevel(final int levelNum, final long bitPattern) {
return ((1L << levelNum) & bitPattern) > 0;
}
private static int getLevelNum(final int k, final int index) {
final int twoK = 2 * k;
return index < twoK ? - 1 : (index - twoK) / k;
}
}