MATH-1268

API for algorithms that create some visualization of a 2D SOFM.

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

@@ -0,0 +1,37 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.math4.ml.neuralnet.twod.util;
+
+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.
+ */
+public interface MapDataVisualization {
+    /**
+     * Creates an image of the {@code data} metrics when represented by the
+     * {@code map}.
+     *
+     * @param map Map.
+     * @param data Data.
+     * @return a 2D-array (in row major order) representing the metrics.
+     */
+    double[][] computeImage(NeuronSquareMesh2D map,
+                            Iterable<double[]> data);
+}

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

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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.math4.ml.neuralnet.twod.util;
+
+import org.apache.commons.math4.ml.neuralnet.twod.NeuronSquareMesh2D;
+
+/**
+ * Interface for algorithms that compute some property of a 2D-map.
+ */
+public interface MapVisualization {
+    /**
+     * Creates an image of the {@code map}.
+     *
+     * @param map Map.
+     * @return a 2D-array (in row major order) representing the property.
+     */
+    double[][] computeImage(NeuronSquareMesh2D map);
+}

src/main/java/org/apache/commons/math4/ml/neuralnet/twod/util/package-info.java

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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * Utilities to visualize two-dimensional neural networks.
+ */
+
+package org.apache.commons.math4.ml.neuralnet.twod.util;