test experimental DJL support

Author: paulk-asert

subprojects/Iris/src/main/groovy/DJLRegressor_WekaXChart.groovy

@@ -0,0 +1,59 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed 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
+ *
+ *     https://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.
+ */
+import org.knowm.xchart.SwingWrapper
+import org.knowm.xchart.XYChartBuilder
+import weka.classifiers.AbstractClassifier
+import weka.core.Utils
+import weka.core.WekaPackageManager
+import weka.core.converters.CSVLoader
+
+import static org.knowm.xchart.XYSeries.XYSeriesRenderStyle.Scatter
+
+WekaPackageManager.loadPackages(true)
+
+def file = getClass().classLoader.getResource('iris_data.csv').file as File
+println file
+def species = ['Iris-setosa', 'Iris-versicolor', 'Iris-virginica']
+def loader = new CSVLoader(file: file)
+def data = loader.dataSet
+data.classIndex = 4
+
+def options = Utils.splitOptions("-S 1")
+AbstractClassifier classifier = Utils.forName(AbstractClassifier, "weka.classifiers.djl.DJLRegressor", options)
+
+double[] actual = data.collect{ it.value(4) }
+double[] predicted = data.collect{ classifier.classifyInstance(it) }
+double[] petalW = data.collect{ it.value(2) }
+double[] petalL = data.collect{ it.value(3) }
+def indices = actual.indices
+
+def chart = new XYChartBuilder().width(900).height(450).
+    title("Species").xAxisTitle("Petal length").yAxisTitle("Petal width").build()
+species.eachWithIndex{ String name, int i ->
+    def groups = indices.findAll{ predicted[it] == i }.groupBy{ actual[it] == i }
+    Collection found = groups[true] ?: []
+    Collection errors = groups[false] ?: []
+    println "$name: ${found.size()} correct, ${errors.size()} incorrect"
+    chart.addSeries("$name correct", petalW[found], petalL[found]).with {
+        XYSeriesRenderStyle = Scatter
+    }
+    if (errors) {
+        chart.addSeries("$name incorrect", petalW[errors], petalL[errors]).with {
+            XYSeriesRenderStyle = Scatter
+        }
+    }
+}
+new SwingWrapper(chart).displayChart()