/*
* 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.
*/
using System;
using Lucene.Net.Index;
using Lucene.Net.Search.Function;
namespace Lucene.Net.Spatial.Util
{
public class ReciprocalFloatFunction : ValueSource
{
protected readonly ValueSource source;
protected readonly float m;
protected readonly float a;
protected readonly float b;
///
/// f(source) = a/(m*float(source)+b)
///
///
///
///
///
public ReciprocalFloatFunction(ValueSource source, float m, float a, float b)
{
this.source = source;
this.m = m;
this.a = a;
this.b = b;
}
public class FloatDocValues : DocValues
{
private readonly ReciprocalFloatFunction _enclosingInstance;
private readonly DocValues vals;
public FloatDocValues(ReciprocalFloatFunction enclosingInstance, DocValues vals)
{
_enclosingInstance = enclosingInstance;
this.vals = vals;
}
public override float FloatVal(int doc)
{
return _enclosingInstance.a / (_enclosingInstance.m * vals.FloatVal(doc) + _enclosingInstance.b);
}
public override string ToString(int doc)
{
return _enclosingInstance.a + "/("
+ _enclosingInstance.m + "*float(" + vals.ToString(doc) + ')'
+ '+' + _enclosingInstance.b + ')';
}
}
public override DocValues GetValues(IndexReader reader)
{
var vals = source.GetValues(reader);
return new FloatDocValues(this, vals);
}
public override string Description()
{
return a + "/("
+ m + "*float(" + source.Description() + ")"
+ "+" + b + ')';
}
public override bool Equals(object o)
{
if (typeof(ReciprocalFloatFunction) != o.GetType()) return false;
var other = (ReciprocalFloatFunction)o;
return this.m == other.m
&& this.a == other.a
&& this.b == other.b
&& this.source.Equals(other.source);
}
public override int GetHashCode()
{
int h = (int) BitConverter.DoubleToInt64Bits(a) + (int) BitConverter.DoubleToInt64Bits(m);
h ^= (h << 13) | (int)((uint)h >> 20);
return h + ((int) BitConverter.DoubleToInt64Bits(b)) + source.GetHashCode();
}
}
}