lucene-java-3.4.0/lucene/contrib/spellchecker/src/test/org/apache/lucene/search/spell/TestNGramDistance.java

   1 package org.apache.lucene.search.spell;
   2
   3 /**
   4  * Licensed to the Apache Software Foundation (ASF) under one or more
   5  * contributor license agreements.  See the NOTICE file distributed with
   6  * this work for additional information regarding copyright ownership.
   7  * The ASF licenses this file to You under the Apache License, Version 2.0
   8  * (the "License"); you may not use this file except in compliance with
   9  * the License.  You may obtain a copy of the License at
  10  *
  11  *     http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  * Unless required by applicable law or agreed to in writing, software
  14  * distributed under the License is distributed on an "AS IS" BASIS,
  15  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  * See the License for the specific language governing permissions and
  17  * limitations under the License.
  18  */
  19
  20 import org.apache.lucene.util.LuceneTestCase;
  21
  22 public class TestNGramDistance extends LuceneTestCase {
  23
  24
  25
  26   public void testGetDistance1() {
  27     StringDistance nsd = new NGramDistance(1);
  28     float d = nsd.getDistance("al", "al");
  29     assertEquals(d,1.0f,0.001);
  30     d = nsd.getDistance("a", "a");
  31     assertEquals(d,1.0f,0.001);
  32     d = nsd.getDistance("b", "a");
  33     assertEquals(d,0.0f,0.001);
  34     d = nsd.getDistance("martha", "marhta");
  35     assertEquals(d,0.6666,0.001);
  36     d = nsd.getDistance("jones", "johnson");
  37     assertEquals(d,0.4285,0.001);
  38     d = nsd.getDistance("natural", "contrary");
  39     assertEquals(d,0.25,0.001);
  40     d = nsd.getDistance("abcvwxyz", "cabvwxyz");
  41     assertEquals(d,0.75,0.001);
  42     d = nsd.getDistance("dwayne", "duane");
  43     assertEquals(d,0.666,0.001);
  44     d = nsd.getDistance("dixon", "dicksonx");
  45     assertEquals(d,0.5,0.001);
  46     d = nsd.getDistance("six", "ten");
  47     assertEquals(d,0,0.001);
  48     float d1 = nsd.getDistance("zac ephron", "zac efron");
  49     float d2 = nsd.getDistance("zac ephron", "kai ephron");
  50     assertEquals(d1,d2,0.001);
  51     d1 = nsd.getDistance("brittney spears", "britney spears");
  52     d2 = nsd.getDistance("brittney spears", "brittney startzman");
  53     assertTrue(d1 > d2);
  54     d1 = nsd.getDistance("12345678", "12890678");
  55     d2 = nsd.getDistance("12345678", "72385698");
  56     assertEquals(d1,d2,001);
  57   }
  58
  59   public void testGetDistance2() {
  60     StringDistance sd = new NGramDistance(2);
  61     float d = sd.getDistance("al", "al");
  62     assertEquals(d,1.0f,0.001);
  63     d = sd.getDistance("a", "a");
  64     assertEquals(d,1.0f,0.001);
  65     d = sd.getDistance("b", "a");
  66     assertEquals(d,0.0f,0.001);
  67     d = sd.getDistance("a", "aa");
  68     assertEquals(d,0.5f,0.001);
  69     d = sd.getDistance("martha", "marhta");
  70     assertEquals(d,0.6666,0.001);
  71     d = sd.getDistance("jones", "johnson");
  72     assertEquals(d,0.4285,0.001);
  73     d = sd.getDistance("natural", "contrary");
  74     assertEquals(d,0.25,0.001);
  75     d = sd.getDistance("abcvwxyz", "cabvwxyz");
  76     assertEquals(d,0.625,0.001);
  77     d = sd.getDistance("dwayne", "duane");
  78     assertEquals(d,0.5833,0.001);
  79     d = sd.getDistance("dixon", "dicksonx");
  80     assertEquals(d,0.5,0.001);
  81     d = sd.getDistance("six", "ten");
  82     assertEquals(d,0,0.001);
  83     float d1 = sd.getDistance("zac ephron", "zac efron");
  84     float d2 = sd.getDistance("zac ephron", "kai ephron");
  85     assertTrue(d1 > d2);
  86     d1 = sd.getDistance("brittney spears", "britney spears");
  87     d2 = sd.getDistance("brittney spears", "brittney startzman");
  88     assertTrue(d1 > d2);
  89     d1 = sd.getDistance("0012345678", "0012890678");
  90     d2 = sd.getDistance("0012345678", "0072385698");
  91     assertEquals(d1,d2,0.001);
  92   }
  93
  94   public void testGetDistance3() {
  95     StringDistance sd = new NGramDistance(3);
  96     float d = sd.getDistance("al", "al");
  97     assertEquals(d,1.0f,0.001);
  98     d = sd.getDistance("a", "a");
  99     assertEquals(d,1.0f,0.001);
 100     d = sd.getDistance("b", "a");
 101     assertEquals(d,0.0f,0.001);
 102     d = sd.getDistance("martha", "marhta");
 103     assertEquals(d,0.7222,0.001);
 104     d = sd.getDistance("jones", "johnson");
 105     assertEquals(d,0.4762,0.001);
 106     d = sd.getDistance("natural", "contrary");
 107     assertEquals(d,0.2083,0.001);
 108     d = sd.getDistance("abcvwxyz", "cabvwxyz");
 109     assertEquals(d,0.5625,0.001);
 110     d = sd.getDistance("dwayne", "duane");
 111     assertEquals(d,0.5277,0.001);
 112     d = sd.getDistance("dixon", "dicksonx");
 113     assertEquals(d,0.4583,0.001);
 114     d = sd.getDistance("six", "ten");
 115     assertEquals(d,0,0.001);
 116     float d1 = sd.getDistance("zac ephron", "zac efron");
 117     float d2 = sd.getDistance("zac ephron", "kai ephron");
 118     assertTrue(d1 > d2);
 119     d1 = sd.getDistance("brittney spears", "britney spears");
 120     d2 = sd.getDistance("brittney spears", "brittney startzman");
 121     assertTrue(d1 > d2);
 122     d1 = sd.getDistance("0012345678", "0012890678");
 123     d2 = sd.getDistance("0012345678", "0072385698");
 124     assertTrue(d1 < d2);
 125   }
 126
 127   public void testEmpty() throws Exception {
 128     StringDistance nsd = new NGramDistance(1);
 129     float d = nsd.getDistance("", "al");
 130     assertEquals(d,0.0f,0.001);
 131   }
 132 }