Added missing @since tags.

src/main/java/org/apache/commons/math4/ml/neuralnet/Network.java

@@ -143,6 +143,7 @@ public class Network
      * Updating one will not affect the other.
      *
      * @return a new instance with the same state as this instance.
+     * @since 3.6
      */
     public synchronized Network copy() {
         final Network copy = new Network(nextId.get(),

src/main/java/org/apache/commons/math4/ml/neuralnet/Neuron.java

@@ -72,6 +72,7 @@ public class Neuron implements Serializable {
      * Updating one will not affect the other.
      *
      * @return a new instance with the same state as this instance.
+     * @since 3.6
      */
     public synchronized Neuron copy() {
         final Neuron copy = new Neuron(getIdentifier(),
@@ -173,6 +174,7 @@ public class Neuron implements Serializable {
      * may be required to ensure consistency.
      *
      * @return the number of update attempts.
+     * @since 3.6
      */
     public long getNumberOfAttemptedUpdates() {
         return numberOfAttemptedUpdates.get();
@@ -187,6 +189,7 @@ public class Neuron implements Serializable {
      * may be required to ensure consistency.
      *
      * @return the number of successful updates.
+     * @since 3.6
      */
     public long getNumberOfSuccessfulUpdates() {
         return numberOfSuccessfulUpdates.get();

src/main/java/org/apache/commons/math4/ml/neuralnet/twod/NeuronSquareMesh2D.java

@@ -68,6 +68,7 @@ public class NeuronSquareMesh2D
 
     /**
      * Horizontal (along row) direction.
+     * @since 3.6
      */
     public enum HorizontalDirection {
         /** Column at the right of the current column. */
@@ -79,6 +80,7 @@ public class NeuronSquareMesh2D
     }
     /**
      * Vertical (along column) direction.
+     * @since 3.6
      */
     public enum VerticalDirection {
         /** Row above the current row. */
@@ -230,6 +232,7 @@ public class NeuronSquareMesh2D
      * Updating one will not affect the other.
      *
      * @return a new instance with the same state as this instance.
+     * @since 3.6
      */
     public synchronized NeuronSquareMesh2D copy() {
         final long[][] idGrid = new long[numberOfRows][numberOfColumns];

src/main/java/org/apache/commons/math4/ml/neuralnet/twod/util/HitHistogram.java

@@ -26,6 +26,7 @@ import org.apache.commons.math4.ml.distance.DistanceMeasure;
  * Computes the hit histogram.
  * Each bin will contain the number of data for which the corresponding
  * neuron is the best matching unit.
+ * @since 3.6
  */
 public class HitHistogram implements MapDataVisualization {
     /** Distance. */

src/main/java/org/apache/commons/math4/ml/neuralnet/twod/util/LocationFinder.java

@@ -25,6 +25,7 @@ import org.apache.commons.math4.exception.MathIllegalStateException;
 
 /**
  * Helper class to find the grid coordinates of a neuron.
+ * @since 3.6
  */
 public class LocationFinder {
     /** Identifier to location mapping. */

src/main/java/org/apache/commons/math4/ml/neuralnet/twod/util/MapDataVisualization.java

@@ -22,6 +22,7 @@ import org.apache.commons.math4.ml.neuralnet.twod.NeuronSquareMesh2D;
 /**
  * Interface for algorithms that compute some metrics of the projection of
  * data on a 2D-map.
+ * @since 3.6
  */
 public interface MapDataVisualization {
     /**

src/main/java/org/apache/commons/math4/ml/neuralnet/twod/util/MapVisualization.java

@@ -21,6 +21,7 @@ import org.apache.commons.math4.ml.neuralnet.twod.NeuronSquareMesh2D;
 
 /**
  * Interface for algorithms that compute some property of a 2D-map.
+ * @since 3.6
  */
 public interface MapVisualization {
     /**

src/main/java/org/apache/commons/math4/ml/neuralnet/twod/util/QuantizationError.java

@@ -26,6 +26,7 @@ import org.apache.commons.math4.ml.distance.DistanceMeasure;
  * Computes the quantization error histogram.
  * Each bin will contain the average of the distances between samples
  * mapped to the corresponding unit and the weight vector of that unit.
+ * @since 3.6
  */
 public class QuantizationError implements MapDataVisualization {
     /** Distance. */

src/main/java/org/apache/commons/math4/ml/neuralnet/twod/util/SmoothedDataHistogram.java

@@ -31,6 +31,7 @@ import org.apache.commons.math4.exception.NumberIsTooSmallException;
  *  <br>
  *  by Elias Pampalk, Andreas Rauber and Dieter Merkl.
  * </quote>
+ * @since 3.6
  */
 public class SmoothedDataHistogram implements MapDataVisualization {
     /** Smoothing parameter. */

src/main/java/org/apache/commons/math4/ml/neuralnet/twod/util/TopographicErrorHistogram.java

@@ -28,6 +28,7 @@ import org.apache.commons.math4.util.Pair;
  * Computes the topographic error histogram.
  * Each bin will contain the number of data for which the first and
  * second best matching units are not adjacent in the map.
+ * @since 3.6
  */
 public class TopographicErrorHistogram implements MapDataVisualization {
     /** Distance. */

src/main/java/org/apache/commons/math4/ml/neuralnet/twod/util/UnifiedDistanceMatrix.java

@@ -26,6 +26,7 @@ import org.apache.commons.math4.ml.distance.DistanceMeasure;
 /**
  * <a href="http://en.wikipedia.org/wiki/U-Matrix">U-Matrix</a>
  * visualization of high-dimensional data projection.
+ * @since 3.6
  */
 public class UnifiedDistanceMatrix implements MapVisualization {
     /** Whether to show distance between each pair of neighbouring units. */

src/main/java/org/apache/commons/math4/util/MathArrays.java

@@ -249,6 +249,7 @@ public class MathArrays {
      * @param v1 Cartesian coordinates of the first vector.
      * @param v2 Cartesian coordinates of the second vector.
      * @return the cosine of the angle between the vectors.
+     * @since 3.6
      */
     public static double cosAngle(double[] v1, double[] v2) {
         return linearCombination(v1, v2) / (safeNorm(v1) * safeNorm(v2));
@@ -391,6 +392,7 @@ public class MathArrays {
      * @return {@code true} if the arrays have the same length.
      * @throws DimensionMismatchException if the lengths differ and
      * {@code abort} is {@code true}.
+     * @since 3.6
      */
     public static boolean checkEqualLength(double[] a,
                                            double[] b,
@@ -411,6 +413,7 @@ public class MathArrays {
      * @param a Array.
      * @param b Array.
      * @throws DimensionMismatchException if the lengths differ.
+     * @since 3.6
      */
     public static void checkEqualLength(double[] a,
                                         double[] b) {
@@ -427,6 +430,7 @@ public class MathArrays {
      * @return {@code true} if the arrays have the same length.
      * @throws DimensionMismatchException if the lengths differ and
      * {@code abort} is {@code true}.
+     * @since 3.6
      */
     public static boolean checkEqualLength(int[] a,
                                            int[] b,
@@ -447,6 +451,7 @@ public class MathArrays {
      * @param a Array.
      * @param b Array.
      * @throws DimensionMismatchException if the lengths differ.
+     * @since 3.6
      */
     public static void checkEqualLength(int[] a,
                                         int[] b) {