Example usage for opennlp.tools.languagemodel NGramLanguageModel calculateProbability

Introduction

In this page you can find the example usage for opennlp.tools.languagemodel NGramLanguageModel calculateProbability.

Prototype

@Override
    public double calculateProbability(String... tokens) 

Source Link

Usage

From source file:opennlp.tools.languagemodel.NgramLanguageModelTest.java

@Test
public void testEmptyVocabularyProbability() throws Exception {
    NGramLanguageModel model = new NGramLanguageModel();
    Assert.assertEquals("probability with an empty vocabulary is always 0", 0d,
            model.calculateProbability(new StringList("")), 0d);
    Assert.assertEquals("probability with an empty vocabulary is always 0", 0d,
            model.calculateProbability(new StringList("1", "2", "3")), 0d);
}

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From source file:opennlp.tools.languagemodel.NgramLanguageModelTest.java

@Test
public void testRandomVocabularyAndSentence() throws Exception {
    NGramLanguageModel model = new NGramLanguageModel();
    for (StringList sentence : LanguageModelTestUtils.generateRandomVocabulary(10)) {
        model.add(sentence, 2, 3);//from  w ww.  j a  v a 2  s  . c om
    }
    double probability = model.calculateProbability(LanguageModelTestUtils.generateRandomSentence());
    Assert.assertTrue("a probability measure should be between 0 and 1 [was " + probability + "]",
            probability >= 0 && probability <= 1);
}

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From source file:opennlp.tools.languagemodel.NgramLanguageModelTest.java

@Test
public void testNgramModel() throws Exception {
    NGramLanguageModel model = new NGramLanguageModel(4);
    model.add(new StringList("I", "saw", "the", "fox"), 1, 4);
    model.add(new StringList("the", "red", "house"), 1, 4);
    model.add(new StringList("I", "saw", "something", "nice"), 1, 2);
    double probability = model.calculateProbability(new StringList("I", "saw", "the", "red", "house"));
    Assert.assertTrue("a probability measure should be between 0 and 1 [was " + probability + "]",
            probability >= 0 && probability <= 1);

    StringList tokens = model.predictNextTokens(new StringList("I", "saw"));
    Assert.assertNotNull(tokens);/*from   w  w  w .j  a v a 2 s . c  om*/
    Assert.assertEquals(new StringList("the", "fox"), tokens);
}

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From source file:opennlp.tools.languagemodel.NgramLanguageModelTest.java

@Test
public void testBigramProbabilityNoSmoothing() throws Exception {
    NGramLanguageModel model = new NGramLanguageModel(2, 0);
    model.add(new StringList("<s>", "I", "am", "Sam", "</s>"), 1, 2);
    model.add(new StringList("<s>", "Sam", "I", "am", "</s>"), 1, 2);
    model.add(new StringList("<s>", "I", "do", "not", "like", "green", "eggs", "and", "ham", "</s>"), 1, 2);
    double probability = model.calculateProbability(new StringList("<s>", "I"));
    Assert.assertEquals(0.666d, probability, 0.001);
    probability = model.calculateProbability(new StringList("Sam", "</s>"));
    Assert.assertEquals(0.5d, probability, 0.001);
    probability = model.calculateProbability(new StringList("<s>", "Sam"));
    Assert.assertEquals(0.333d, probability, 0.001);
    probability = model.calculateProbability(new StringList("am", "Sam"));
    Assert.assertEquals(0.5d, probability, 0.001);
    probability = model.calculateProbability(new StringList("I", "am"));
    Assert.assertEquals(0.666d, probability, 0.001);
    probability = model.calculateProbability(new StringList("I", "do"));
    Assert.assertEquals(0.333d, probability, 0.001);
    probability = model.calculateProbability(new StringList("I", "am", "Sam"));
    Assert.assertEquals(0.333d, probability, 0.001);
}

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From source file:opennlp.tools.languagemodel.NgramLanguageModelTest.java

@Test
public void testTrigram() throws Exception {
    NGramLanguageModel model = new NGramLanguageModel(3);
    model.add(new StringList("I", "see", "the", "fox"), 2, 3);
    model.add(new StringList("the", "red", "house"), 2, 3);
    model.add(new StringList("I", "saw", "something", "nice"), 2, 3);
    double probability = model.calculateProbability(new StringList("I", "saw", "the", "red", "house"));
    Assert.assertTrue("a probability measure should be between 0 and 1 [was " + probability + "]",
            probability >= 0 && probability <= 1);

    StringList tokens = model.predictNextTokens(new StringList("I", "saw"));
    Assert.assertNotNull(tokens);//from   ww w .jav  a 2 s  .  c  o  m
    Assert.assertEquals(new StringList("something", "nice"), tokens);
}

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From source file:opennlp.tools.languagemodel.NgramLanguageModelTest.java

@Test
public void testBigram() throws Exception {
    NGramLanguageModel model = new NGramLanguageModel(2);
    model.add(new StringList("I", "see", "the", "fox"), 1, 2);
    model.add(new StringList("the", "red", "house"), 1, 2);
    model.add(new StringList("I", "saw", "something", "nice"), 1, 2);
    double probability = model.calculateProbability(new StringList("I", "saw", "the", "red", "house"));
    Assert.assertTrue("a probability measure should be between 0 and 1 [was " + probability + "]",
            probability >= 0 && probability <= 1);

    StringList tokens = model.predictNextTokens(new StringList("I", "saw"));
    Assert.assertNotNull(tokens);/*from   w  w  w .j  av  a  2s .c  o m*/
    Assert.assertEquals(new StringList("something"), tokens);
}

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From source file:opennlp.tools.languagemodel.NgramLanguageModelTest.java

@Test
public void testSerializedNGramLanguageModel() throws Exception {
    NGramLanguageModel languageModel = new NGramLanguageModel(
            getClass().getResourceAsStream("/opennlp/tools/ngram/ngram-model.xml"), 3);
    double probability = languageModel.calculateProbability(new StringList("The", "brown", "fox", "jumped"));
    Assert.assertTrue("a probability measure should be between 0 and 1 [was " + probability + "]",
            probability >= 0 && probability <= 1);
    StringList tokens = languageModel.predictNextTokens(new StringList("fox"));
    Assert.assertNotNull(tokens);/*  w ww  .ja  va  2s  . c o m*/
    Assert.assertEquals(new StringList("jumped"), tokens);
}

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From source file:opennlp.tools.languagemodel.NgramLanguageModelTest.java

@Test
public void testTrigramLanguageModelCreationFromText() throws Exception {
    int ngramSize = 3;
    NGramLanguageModel languageModel = new NGramLanguageModel(ngramSize);
    InputStream stream = getClass().getResourceAsStream("/opennlp/tools/languagemodel/sentences.txt");
    for (String line : IOUtils.readLines(stream)) {
        String[] array = line.split(" ");
        List<String> split = Arrays.asList(array);
        List<String> generatedStrings = NGramGenerator.generate(split, ngramSize, " ");
        for (String generatedString : generatedStrings) {
            String[] tokens = generatedString.split(" ");
            if (tokens.length > 0) {
                languageModel.add(new StringList(tokens), 1, ngramSize);
            }/*  www.  j  a va  2 s  .co m*/
        }
    }
    StringList tokens = languageModel.predictNextTokens(new StringList("neural", "network", "language"));
    Assert.assertNotNull(tokens);
    Assert.assertEquals(new StringList("models"), tokens);
    double p1 = languageModel.calculateProbability(new StringList("neural", "network", "language", "models"));
    double p2 = languageModel.calculateProbability(new StringList("neural", "network", "language", "model"));
    Assert.assertTrue(p1 > p2);
}

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