Examples with KMeansModel de.lmu.ifi.dbs.elki.data.model.KMeansModel used on opensource projects

Example 16 with KMeansModel

use of de.lmu.ifi.dbs.elki.data.model.KMeansModel in project elki by elki-project.

the class WithinClusterVarianceQualityMeasureTest method testVariance.

/**
 * Test cluster variance.
 */
@Test
public void testVariance() {
    Database db = makeSimpleDatabase(UNITTEST + "quality-measure-test.csv", 7);
    Relation<DoubleVector> rel = db.getRelation(TypeUtil.DOUBLE_VECTOR_FIELD);
    // Setup algorithm
    KMeansLloyd<DoubleVector> kmeans = // 
    new ELKIBuilder<KMeansLloyd<DoubleVector>>(KMeansLloyd.class).with(KMeans.K_ID, // 
    2).with(KMeans.INIT_ID, // 
    FirstKInitialMeans.class).build();
    // run KMeans on database
    Clustering<KMeansModel> result = kmeans.run(db);
    // Test Cluster Variance
    KMeansQualityMeasure<? super DoubleVector> variance = new WithinClusterVarianceQualityMeasure();
    final NumberVectorDistanceFunction<? super DoubleVector> dist = kmeans.getDistanceFunction();
    final double quality = variance.quality(result, dist, rel);
    assertEquals("Within cluster variance incorrect", 3.16666666666, quality, 1e-10);
}