--- a/artifacts/src/main/java/org/dive4elements/river/utils/DoubleUtil.java	Fri Jul 18 11:16:50 2014 +0200
+++ b/artifacts/src/main/java/org/dive4elements/river/utils/DoubleUtil.java	Fri Jul 18 11:58:59 2014 +0200
@@ -171,6 +171,14 @@
         return out;
     }
 
+    public static final double sum(double [] values) {
+        double sum = 0.0;
+        for (double value: values) {
+            sum += value;
+        }
+        return sum;
+    }
+
     public static final double [] fill(int N, double value) {
         double [] result = new double[N];
         Arrays.fill(result, value);
@@ -234,6 +242,15 @@
         return true;
     }
 
+    public static final boolean isNaN(double [] values) {
+        for (double value: values) {
+            if (!Double.isNaN(value)) {
+                return false;
+            }
+        }
+        return true;
+    }
+
     /** In an array of doubles, search and return the maximum value. */
     public static final double maxInArray(double[] values) {
         double max = - Double.MAX_VALUE;