/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.search.aggregations.metrics.stats.extended;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.xcontent.XContentBuilder;
import org.elasticsearch.search.DocValueFormat;
import org.elasticsearch.search.aggregations.InternalAggregation;
import org.elasticsearch.search.aggregations.metrics.stats.InternalStats;
import org.elasticsearch.search.aggregations.pipeline.PipelineAggregator;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import java.util.Objects;
public class InternalExtendedStats extends InternalStats implements ExtendedStats {
enum Metrics {
count, sum, min, max, avg, sum_of_squares, variance, std_deviation, std_upper, std_lower;
public static Metrics resolve(String name) {
return Metrics.valueOf(name);
}
}
private final double sumOfSqrs;
private final double sigma;
public InternalExtendedStats(String name, long count, double sum, double min, double max, double sumOfSqrs, double sigma,
DocValueFormat formatter, List<PipelineAggregator> pipelineAggregators, Map<String, Object> metaData) {
super(name, count, sum, min, max, formatter, pipelineAggregators, metaData);
this.sumOfSqrs = sumOfSqrs;
this.sigma = sigma;
}
/**
* Read from a stream.
*/
public InternalExtendedStats(StreamInput in) throws IOException {
super(in);
sumOfSqrs = in.readDouble();
sigma = in.readDouble();
}
@Override
protected void writeOtherStatsTo(StreamOutput out) throws IOException {
out.writeDouble(sumOfSqrs);
out.writeDouble(sigma);
}
@Override
public String getWriteableName() {
return ExtendedStatsAggregationBuilder.NAME;
}
@Override
public double value(String name) {
if ("sum_of_squares".equals(name)) {
return sumOfSqrs;
}
if ("variance".equals(name)) {
return getVariance();
}
if ("std_deviation".equals(name)) {
return getStdDeviation();
}
if ("std_upper".equals(name)) {
return getStdDeviationBound(Bounds.UPPER);
}
if ("std_lower".equals(name)) {
return getStdDeviationBound(Bounds.LOWER);
}
return super.value(name);
}
public double getSigma() {
return this.sigma;
}
@Override
public double getSumOfSquares() {
return sumOfSqrs;
}
@Override
public double getVariance() {
return (sumOfSqrs - ((sum * sum) / count)) / count;
}
@Override
public double getStdDeviation() {
return Math.sqrt(getVariance());
}
@Override
public double getStdDeviationBound(Bounds bound) {
if (bound.equals(Bounds.UPPER)) {
return getAvg() + (getStdDeviation() * sigma);
} else {
return getAvg() - (getStdDeviation() * sigma);
}
}
@Override
public String getSumOfSquaresAsString() {
return valueAsString(Metrics.sum_of_squares.name());
}
@Override
public String getVarianceAsString() {
return valueAsString(Metrics.variance.name());
}
@Override
public String getStdDeviationAsString() {
return valueAsString(Metrics.std_deviation.name());
}
@Override
public String getStdDeviationBoundAsString(Bounds bound) {
return bound == Bounds.UPPER ? valueAsString(Metrics.std_upper.name()) : valueAsString(Metrics.std_lower.name());
}
@Override
public InternalExtendedStats doReduce(List<InternalAggregation> aggregations, ReduceContext reduceContext) {
double sumOfSqrs = 0;
for (InternalAggregation aggregation : aggregations) {
InternalExtendedStats stats = (InternalExtendedStats) aggregation;
if (stats.sigma != sigma) {
throw new IllegalStateException("Cannot reduce other stats aggregations that have a different sigma");
}
sumOfSqrs += stats.getSumOfSquares();
}
final InternalStats stats = super.doReduce(aggregations, reduceContext);
return new InternalExtendedStats(name, stats.getCount(), stats.getSum(), stats.getMin(), stats.getMax(), sumOfSqrs, sigma,
format, pipelineAggregators(), getMetaData());
}
static class Fields {
public static final String SUM_OF_SQRS = "sum_of_squares";
public static final String SUM_OF_SQRS_AS_STRING = "sum_of_squares_as_string";
public static final String VARIANCE = "variance";
public static final String VARIANCE_AS_STRING = "variance_as_string";
public static final String STD_DEVIATION = "std_deviation";
public static final String STD_DEVIATION_AS_STRING = "std_deviation_as_string";
public static final String STD_DEVIATION_BOUNDS = "std_deviation_bounds";
public static final String STD_DEVIATION_BOUNDS_AS_STRING = "std_deviation_bounds_as_string";
public static final String UPPER = "upper";
public static final String LOWER = "lower";
}
@Override
protected XContentBuilder otherStatsToXCotent(XContentBuilder builder, Params params) throws IOException {
builder.field(Fields.SUM_OF_SQRS, count != 0 ? sumOfSqrs : null);
builder.field(Fields.VARIANCE, count != 0 ? getVariance() : null);
builder.field(Fields.STD_DEVIATION, count != 0 ? getStdDeviation() : null);
builder.startObject(Fields.STD_DEVIATION_BOUNDS)
.field(Fields.UPPER, count != 0 ? getStdDeviationBound(Bounds.UPPER) : null)
.field(Fields.LOWER, count != 0 ? getStdDeviationBound(Bounds.LOWER) : null)
.endObject();
if (count != 0 && format != DocValueFormat.RAW) {
builder.field(Fields.SUM_OF_SQRS_AS_STRING, format.format(sumOfSqrs));
builder.field(Fields.VARIANCE_AS_STRING, format.format(getVariance()));
builder.field(Fields.STD_DEVIATION_AS_STRING, getStdDeviationAsString());
builder.startObject(Fields.STD_DEVIATION_BOUNDS_AS_STRING)
.field(Fields.UPPER, getStdDeviationBoundAsString(Bounds.UPPER))
.field(Fields.LOWER, getStdDeviationBoundAsString(Bounds.LOWER))
.endObject();
}
return builder;
}
@Override
protected int doHashCode() {
return Objects.hash(super.doHashCode(), sumOfSqrs, sigma);
}
@Override
protected boolean doEquals(Object obj) {
InternalExtendedStats other = (InternalExtendedStats) obj;
return super.doEquals(obj) &&
Double.compare(sumOfSqrs, other.sumOfSqrs) == 0 &&
Double.compare(sigma, other.sigma) == 0;
}
}