org.apache.solr.search.function.distance.HaversineFunction Maven / Gradle / Ivy
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* 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.solr.search.function.distance;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.queries.function.FunctionValues;
import org.apache.lucene.queries.function.ValueSource;
import org.apache.lucene.queries.function.docvalues.DoubleDocValues;
import org.apache.lucene.queries.function.valuesource.MultiValueSource;
import org.apache.lucene.search.IndexSearcher;
import org.locationtech.spatial4j.distance.DistanceUtils;
import org.apache.solr.common.SolrException;
import java.io.IOException;
import java.util.Map;
/**
* Calculate the Haversine formula (distance) between any two points on a sphere
* Takes in four value sources: (latA, lonA); (latB, lonB).
*
* Assumes the value sources are in radians unless
*
* See http://en.wikipedia.org/wiki/Great-circle_distance and
* http://en.wikipedia.org/wiki/Haversine_formula for the actual formula and
* also http://www.movable-type.co.uk/scripts/latlong.html
*/
public class HaversineFunction extends ValueSource {
private MultiValueSource p1;
private MultiValueSource p2;
private boolean convertToRadians = false;
private double radius;
public HaversineFunction(MultiValueSource p1, MultiValueSource p2, double radius) {
this(p1, p2, radius, false);
}
public HaversineFunction(MultiValueSource p1, MultiValueSource p2, double radius, boolean convertToRads){
this.p1 = p1;
this.p2 = p2;
if (p1.dimension() != 2 || p2.dimension() != 2) {
throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, "Illegal dimension for value sources");
}
this.radius = radius;
this.convertToRadians = convertToRads;
}
protected String name() {
return "hsin";
}
/**
* @param doc The doc to score
* @return The haversine distance formula
*/
protected double distance(int doc, FunctionValues p1DV, FunctionValues p2DV) throws IOException {
double[] p1D = new double[2];
double[] p2D = new double[2];
p1DV.doubleVal(doc, p1D);
p2DV.doubleVal(doc, p2D);
double y1;
double x1;
double y2;
double x2;
if (convertToRadians) {
y1 = p1D[0] * DistanceUtils.DEGREES_TO_RADIANS;
x1 = p1D[1] * DistanceUtils.DEGREES_TO_RADIANS;
y2 = p2D[0] * DistanceUtils.DEGREES_TO_RADIANS;
x2 = p2D[1] * DistanceUtils.DEGREES_TO_RADIANS;
} else {
y1 = p1D[0];
x1 = p1D[1];
y2 = p2D[0];
x2 = p2D[1];
}
return DistanceUtils.distHaversineRAD(y1,x1,y2,x2)*radius;
}
@Override
public FunctionValues getValues(@SuppressWarnings({"rawtypes"})Map context, LeafReaderContext readerContext) throws IOException {
@SuppressWarnings({"unchecked"})
final FunctionValues vals1 = p1.getValues(context, readerContext);
@SuppressWarnings({"unchecked"})
final FunctionValues vals2 = p2.getValues(context, readerContext);
return new DoubleDocValues(this) {
@Override
public double doubleVal(int doc) throws IOException {
return distance(doc, vals1, vals2);
}
@Override
public String toString(int doc) throws IOException {
StringBuilder sb = new StringBuilder();
sb.append(name()).append('(');
sb.append(vals1.toString(doc)).append(',').append(vals2.toString(doc));
sb.append(')');
return sb.toString();
}
};
}
@Override
@SuppressWarnings({"unchecked"})
public void createWeight(@SuppressWarnings({"rawtypes"})Map context, IndexSearcher searcher) throws IOException {
p1.createWeight(context, searcher);
p2.createWeight(context, searcher);
}
@Override
public boolean equals(Object o) {
if (this.getClass() != o.getClass()) return false;
HaversineFunction other = (HaversineFunction) o;
return this.name().equals(other.name())
&& p1.equals(other.p1) &&
p2.equals(other.p2) && radius == other.radius;
}
@Override
public int hashCode() {
int result;
long temp;
result = p1.hashCode();
result = 31 * result + p2.hashCode();
result = 31 * result + name().hashCode();
temp = Double.doubleToRawLongBits(radius);
result = 31 * result + (int) (temp ^ (temp >>> 32));
return result;
}
@Override
public String description() {
StringBuilder sb = new StringBuilder();
sb.append(name()).append('(');
sb.append(p1).append(',').append(p2);
sb.append(')');
return sb.toString();
}
}