/*
* Cloud9: A MapReduce Library for Hadoop
*
* Licensed 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 edu.umd.cloud9.util.fd;
import it.unimi.dsi.fastutil.ints.Int2IntMap;
import it.unimi.dsi.fastutil.ints.Int2IntOpenHashMap;
import it.unimi.dsi.fastutil.ints.IntCollection;
import it.unimi.dsi.fastutil.ints.IntSet;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import com.google.common.collect.Lists;
import edu.umd.cloud9.io.pair.PairOfInts;
/**
* Implementation of {@link Int2IntFrequencyDistribution} based on
* {@link Int2IntOpenHashMap}.
*
* @author Jimmy Lin
*/
public class Int2IntFrequencyDistributionFastutil implements Int2IntFrequencyDistribution {
private Int2IntOpenHashMap counts = new Int2IntOpenHashMap();
private long sumOfCounts = 0;
@Override
public void increment(int key) {
if (contains(key)) {
set(key, get(key) + 1);
} else {
set(key, 1);
}
}
@Override
public void increment(int key, int cnt) {
if (contains(key)) {
set(key, get(key) + cnt);
} else {
set(key, cnt);
}
}
@Override
public void decrement(int key) {
if (contains(key)) {
int v = get(key);
if (v == 1) {
remove(key);
} else {
set(key, v - 1);
}
} else {
throw new RuntimeException("Can't decrement non-existent event!");
}
}
@Override
public void decrement(int key, int cnt) {
if (contains(key)) {
int v = get(key);
if (v < cnt) {
throw new RuntimeException("Can't decrement past zero!");
} else if (v == cnt) {
remove(key);
} else {
set(key, v - cnt);
}
} else {
throw new RuntimeException("Can't decrement non-existent event!");
}
}
@Override
public boolean contains(int key) {
return counts.containsKey(key);
}
@Override
public int get(int key) {
return counts.get(key);
}
@Override
public double computeRelativeFrequency(int k) {
return (double) counts.get(k) / getSumOfCounts();
}
@Override
public double computeLogRelativeFrequency(int k) {
return Math.log(counts.get(k)) - Math.log(getSumOfCounts());
}
@Override
public int set(int key, int cnt) {
int rv = counts.put(key, cnt);
sumOfCounts = sumOfCounts - rv + cnt;
return rv;
}
@Override
public int remove(int key) {
int rv = counts.remove(key);
sumOfCounts -= rv;
return rv;
}
@Override
public void clear() {
counts.clear();
sumOfCounts = 0;
}
/**
* Exposes efficient method for accessing keys in this map.
*/
public IntSet keySet() {
return counts.keySet();
}
/**
* Exposes efficient method for accessing values in this map.
*/
public IntCollection values() {
return counts.values();
}
/**
* Exposes efficient method for accessing mappings in this map.
*/
public Int2IntMap.FastEntrySet entrySet() {
return counts.int2IntEntrySet();
}
@Override
public int getNumberOfEvents() {
return counts.size();
}
@Override
public long getSumOfCounts() {
return sumOfCounts;
}
/**
* Iterator returns the same object every time, just with a different payload.
*/
public Iterator<PairOfInts> iterator() {
return new Iterator<PairOfInts>() {
private Iterator<Int2IntMap.Entry> iter = Int2IntFrequencyDistributionFastutil.this.counts.int2IntEntrySet().iterator();
private final PairOfInts pair = new PairOfInts();
@Override
public boolean hasNext() {
return iter.hasNext();
}
@Override
public PairOfInts next() {
if (!hasNext()) {
return null;
}
Int2IntMap.Entry entry = iter.next();
pair.set(entry.getIntKey(), entry.getIntValue());
return pair;
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
};
}
@Override
public List<PairOfInts> getEntries(Order ordering) {
if (ordering.equals(Order.ByRightElementDescending)) {
return getEntriesSorted(comparatorRightDescending);
} else if (ordering.equals(Order.ByLeftElementAscending)) {
return getEntriesSorted(comparatorLeftAscending);
} else if (ordering.equals(Order.ByRightElementAscending)) {
return getEntriesSorted(comparatorRightAscending);
} else if (ordering.equals(Order.ByLeftElementDescending)) {
return getEntriesSorted(comparatorLeftDescending);
}
// Should never get here.
return null; }
@Override
public List<PairOfInts> getEntries(Order ordering, int n) {
if (ordering.equals(Order.ByRightElementDescending)) {
return getEntriesSorted(comparatorRightDescending, n);
} else if (ordering.equals(Order.ByLeftElementAscending)) {
return getEntriesSorted(comparatorLeftAscending, n);
} else if (ordering.equals(Order.ByRightElementAscending)) {
return getEntriesSorted(comparatorRightAscending, n);
} else if (ordering.equals(Order.ByLeftElementDescending)) {
return getEntriesSorted(comparatorLeftDescending, n);
}
// Should never get here.
return null;
}
private final Comparator<PairOfInts> comparatorRightDescending = new Comparator<PairOfInts>() {
public int compare(PairOfInts e1, PairOfInts e2) {
if (e1.getRightElement() > e2.getRightElement()) {
return -1;
}
if (e1.getRightElement() < e2.getRightElement()) {
return 1;
}
if (e1.getLeftElement() == e2.getLeftElement()) {
throw new RuntimeException("Event observed twice!");
}
return e1.getLeftElement() < e2.getLeftElement() ? -1 : 1;
}
};
private final Comparator<PairOfInts> comparatorRightAscending = new Comparator<PairOfInts>() {
public int compare(PairOfInts e1, PairOfInts e2) {
if (e1.getRightElement() > e2.getRightElement()) {
return 1;
}
if (e1.getRightElement() < e2.getRightElement()) {
return -1;
}
if (e1.getLeftElement() == e2.getLeftElement()) {
throw new RuntimeException("Event observed twice!");
}
return e1.getLeftElement() < e2.getLeftElement() ? -1 : 1;
}
};
private final Comparator<PairOfInts> comparatorLeftAscending = new Comparator<PairOfInts>() {
public int compare(PairOfInts e1, PairOfInts e2) {
if (e1.getLeftElement() > e2.getLeftElement()) {
return 1;
}
if (e1.getLeftElement() < e2.getLeftElement()) {
return -1;
}
throw new RuntimeException("Event observed twice!");
}
};
private final Comparator<PairOfInts> comparatorLeftDescending = new Comparator<PairOfInts>() {
public int compare(PairOfInts e1, PairOfInts e2) {
if (e1.getLeftElement() > e2.getLeftElement()) {
return -1;
}
if (e1.getLeftElement() < e2.getLeftElement()) {
return 1;
}
throw new RuntimeException("Event observed twice!");
}
};
private List<PairOfInts> getEntriesSorted(Comparator<PairOfInts> comparator) {
List<PairOfInts> list = Lists.newArrayList();
for (Int2IntMap.Entry e : counts.int2IntEntrySet()) {
list.add(new PairOfInts(e.getIntKey(), e.getIntValue()));
}
Collections.sort(list, comparator);
return list;
}
private List<PairOfInts> getEntriesSorted(Comparator<PairOfInts> comparator, int n) {
List<PairOfInts> list = getEntriesSorted(comparator);
return list.subList(0, n);
}
}