MATH-815

Added method that was missing in the original commit: "getDimensions()",
renamed to "getDimension()".


git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1400017 13f79535-47bb-0310-9956-ffa450edef68

src/main/java/org/apache/commons/math3/distribution/AbstractMultivariateRealDistribution.java

@@ -31,7 +31,7 @@ public abstract class AbstractMultivariateRealDistribution
     /** RNG instance used to generate samples from the distribution. */
     protected final RandomGenerator random;
     /** The number of dimensions or columns in the multivariate distribution. */
-    private final int numDimensions;
+    private final int dimension;
 
     /**
      * @param rng Random number generator.
@@ -40,7 +40,7 @@ public abstract class AbstractMultivariateRealDistribution
     protected AbstractMultivariateRealDistribution(RandomGenerator rng,
                                                    int n) {
         random = rng;
-        numDimensions = n;
+        dimension = n;
     }
 
     /** {@inheritDoc} */
@@ -48,14 +48,9 @@ public abstract class AbstractMultivariateRealDistribution
         random.setSeed(seed);
     }
 
-    /**
+    /** {@inheritDoc} */
-     * Gets the number of dimensions (i.e. the number of random variables) of
+    public int getDimension() {
-     * the distribution.
+        return dimension;
-     *
-     * @return the number of dimensions.
-     */
-    public int getDimensions() {
-        return numDimensions;
     }
 
     /** {@inheritDoc} */
@@ -67,7 +62,7 @@ public abstract class AbstractMultivariateRealDistribution
             throw new NotStrictlyPositiveException(LocalizedFormats.NUMBER_OF_SAMPLES,
                                                    sampleSize);
         }
-        final double[][] out = new double[sampleSize][numDimensions];
+        final double[][] out = new double[sampleSize][dimension];
         for (int i = 0; i < sampleSize; i++) {
             out[i] = sample();
         }

src/main/java/org/apache/commons/math3/distribution/MultivariateNormalDistribution.java

@@ -175,7 +175,7 @@ public class MultivariateNormalDistribution
 
     /** {@inheritDoc} */
     public double density(final double[] vals) throws DimensionMismatchException {
-        final int dim = getDimensions();
+        final int dim = getDimension();
         if (vals.length != dim) {
             throw new DimensionMismatchException(vals.length, dim);
         }
@@ -192,7 +192,7 @@ public class MultivariateNormalDistribution
      * @return the standard deviations.
      */
     public double[] getStandardDeviations() {
-        final int dim = getDimensions();
+        final int dim = getDimension();
         final double[] std = new double[dim];
         final double[][] s = covarianceMatrix.getData();
         for (int i = 0; i < dim; i++) {
@@ -203,7 +203,7 @@ public class MultivariateNormalDistribution
 
     /** {@inheritDoc} */
     public double[] sample() {
-        final int dim = getDimensions();
+        final int dim = getDimension();
         final double[] normalVals = new double[dim];
 
         for (int i = 0; i < dim; i++) {

src/main/java/org/apache/commons/math3/distribution/MultivariateRealDistribution.java

@@ -49,6 +49,15 @@ public interface MultivariateRealDistribution {
      */
     void reseedRandomGenerator(long seed);
 
+    /**
+     * Gets the number of random variables of the distribution.
+     * It is the size of the array returned by the {@link #sample() sample}
+     * method.
+     *
+     * @return the number of variables.
+     */
+    int getDimension();
+
     /**
      * Generates a random value vector sampled from this distribution.
      *
@@ -63,6 +72,8 @@ public interface MultivariateRealDistribution {
      * @return an array representing the random samples.
      * @throws org.apache.commons.math3.exception.NotStrictlyPositiveException
      * if {@code sampleSize} is not positive.
+     *
+     * @see #sample()
      */
     double[][] sample(int sampleSize) throws NotStrictlyPositiveException;
 }

src/test/java/org/apache/commons/math3/distribution/MultivariateNormalDistributionTest.java

@@ -56,7 +56,7 @@ public class MultivariateNormalDistributionTest {
         final MultivariateNormalDistribution d = new MultivariateNormalDistribution(mu, sigma);
 
         final RealMatrix s = d.getCovariances();
-        final int dim = d.getDimensions();
+        final int dim = d.getDimension();
         for (int i = 0; i < dim; i++) {
             for (int j = 0; j < dim; j++) {
                 Assert.assertEquals(sigma[i][j], s.getEntry(i, j), 0);
@@ -78,7 +78,7 @@ public class MultivariateNormalDistributionTest {
         final int n = 500000;
 
         final double[][] samples = d.sample(n);
-        final int dim = d.getDimensions();
+        final int dim = d.getDimension();
         final double[] sampleMeans = new double[dim];
 
         for (int i = 0; i < samples.length; i++) {