Added mimMax function

pom.xml

@@ -4,7 +4,7 @@
     <groupId>net.iponweb.disthene.reader</groupId>
     <artifactId>disthene-reader</artifactId>
     <packaging>jar</packaging>
-    <version>1.0.22</version>
+    <version>1.0.23</version>
     <name>disthene-reader</name>
     <url>http://maven.apache.org</url>
     <dependencies>

src/main/java/net/iponweb/disthene/reader/graphite/functions/MinMaxFunction.java

@@ -0,0 +1,59 @@
+package net.iponweb.disthene.reader.graphite.functions;
+
+import net.iponweb.disthene.reader.beans.TimeSeries;
+import net.iponweb.disthene.reader.exceptions.EvaluationException;
+import net.iponweb.disthene.reader.exceptions.InvalidArgumentException;
+import net.iponweb.disthene.reader.exceptions.TimeSeriesNotAlignedException;
+import net.iponweb.disthene.reader.graphite.Target;
+import net.iponweb.disthene.reader.graphite.evaluation.TargetEvaluator;
+import net.iponweb.disthene.reader.utils.CollectionUtils;
+import net.iponweb.disthene.reader.utils.TimeSeriesUtils;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * @author Andrei Ivanov
+ */
+public class MinMaxFunction extends DistheneFunction {
+
+    public MinMaxFunction(String text) {
+        super(text, "minMax");
+    }
+
+    @Override
+    public List<TimeSeries> evaluate(TargetEvaluator evaluator) throws EvaluationException {
+        List<TimeSeries> processedArguments = new ArrayList<>(evaluator.eval((Target) arguments.get(0)));
+
+        if (processedArguments.size() == 0) return new ArrayList<>();
+
+        if (!TimeSeriesUtils.checkAlignment(processedArguments)) {
+            throw new TimeSeriesNotAlignedException();
+        }
+
+        int length = processedArguments.get(0).getValues().length;
+
+        for (TimeSeries ts : processedArguments) {
+            Double min = CollectionUtils.min(Arrays.asList(ts.getValues()));
+            Double max = CollectionUtils.max(Arrays.asList(ts.getValues()));
+            if (min != null && max != null) {
+                double range = max - min;
+                for (int i = 0; i < length; i++) {
+                    if (ts.getValues()[i] != null ) {
+                        ts.getValues()[i] = (ts.getValues()[i] - min) / range;
+                    }
+                }
+            }
+            setResultingName(ts);
+        }
+
+        return processedArguments;
+    }
+
+    @Override
+    public void checkArguments() throws InvalidArgumentException {
+        if (arguments.size() != 1) throw new InvalidArgumentException("minMax: number of arguments is " + arguments.size() + ". Must be one.");
+        if (!(arguments.get(0) instanceof Target)) throw new InvalidArgumentException("minMax: argument is " + arguments.get(0).getClass().getName() + ". Must be series");
+    }
+}

src/main/java/net/iponweb/disthene/reader/graphite/functions/registry/FunctionRegistry.java

@@ -73,6 +73,7 @@ public class FunctionRegistry {
         registry.put("maximumBelow", MaximumBelowFunction.class);
         registry.put("minimumAbove", MinimumAboveFunction.class);
         registry.put("minimumBelow", MinimumBelowFunction.class);
+        registry.put("minMax", MinMaxFunction.class);
         registry.put("maxSeries", MaxSeriesFunction.class);
         registry.put("minSeries", MinSeriesFunction.class);
         registry.put("mostDeviant", MostDeviantFunction.class);