1 package net.obsearch.index;
2 /*
3 OBSearch: a distributed similarity search engine This project is to
4 similarity search what 'bit-torrent' is to downloads.
5 Copyright (C) 2008 Arnoldo Jose Muller Molina
6
7 This program is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>.
19 */
20 import java.io.IOException;
21 import net.obsearch.constants.ByteConstants;
22 import net.obsearch.exception.OBException;
23 import net.obsearch.ob.OBFloat;
24 import java.nio.ByteBuffer;
25 import net.obsearch.utils.bytes.ByteBufferFactoryConversion;
26 import java.util.Random;
27 import java.util.Arrays;
28 /**
29 * L1 distance implementation for floats.
30 * @author Arnoldo Jose Muller Molina
31 *
32 */
33 //*************************************************************************
34 //****** Warning: this is a generated file ********************************
35 //****** The source file is: OBVector.java
36 //*************************************************************************
37 public class OBVectorFloat implements OBFloat {
38
39 private float[] data;
40
41 /**
42 * Default constructor must be provided by every object that implements the
43 * interface OB.
44 */
45 public OBVectorFloat() {
46 data = null;
47 }
48
49 public OBVectorFloat(float[] data){
50 this.data = data;
51 }
52
53 /**
54 * Creates a new vector with dim dimensions created by Random.nextFloat()
55 */
56 public OBVectorFloat(Random r, int dim){
57 int i = 0;
58 data = new float[dim];
59 while(i < dim){
60 data[i] = r.nextFloat();
61
62 i++;
63 }
64 }
65
66 public boolean equals(Object o){
67 OBVectorFloat other = ( OBVectorFloat) o;
68 return Arrays.equals(data, other.data);
69 }
70
71
72 @Override
73 public float distance(OBFloat object) throws OBException {
74 // TODO Auto-generated method stub
75 OBVectorFloat o = (OBVectorFloat) object;
76 assert data.length == o.data.length;
77 float res = 0;
78 int i = 0;
79 while(i < data.length){
80 assert (data[i] - o.data[i]) >= Float.NEGATIVE_INFINITY
81 && (data[i] - o.data[i]) <= Float.MAX_VALUE : "a: " + data[i] + " b: " + o.data[i] ;
82
83
84 res += Math.abs(data[i] - o.data[i]);
85 i++;
86 }
87 return res;
88 }
89
90 //*************************************************************************
91 //****** Warning: this is a generated file ********************************
92 //****** The source file is: OBVector.java
93 //*************************************************************************
94 @Override
95 public void load(byte[] input) throws OBException, IOException {
96 ByteBuffer in = ByteBufferFactoryConversion.createByteBuffer(input);
97 int size = in.getInt();
98
99 data = new float[size];
100 int i = 0;
101 while(i < size){
102 data[i] = in.getFloat();
103 i++;
104 }
105 }
106
107 //*************************************************************************
108 //****** Warning: this is a generated file ********************************
109 //****** The source file is: OBVector.java
110 //*************************************************************************
111 @Override
112 public byte[] store() throws OBException, IOException {
113 ByteBuffer out = ByteBufferFactoryConversion.createByteBuffer(ByteConstants.Float.getSize() * data.length + ByteConstants.Int.getSize() );
114
115 out.putInt(data.length);
116 for(float v : data){
117 out.putFloat(v);
118 }
119 return out.array();
120 }
121
122 }
123