changing divisor to double

tree-water-demand/src/main/java/de/hft/stuttgart/water/TreeWaterDemand.java

@@ -229,8 +229,8 @@ public class TreeWaterDemand {
 		double omegas = Math.acos(-Math.tan(phi) * Math.tan(delta));
 		double ra = 0;
 		if (!(omega < -omegas || omega > omegas)) {
-			double omega1 = omega - Math.PI * 1 / 24;
-			double omega2 = omega + Math.PI * 1 / 24;
+			double omega1 = omega - Math.PI * 1 / 24d;
+			double omega2 = omega + Math.PI * 1 / 24d;
 			ra = 12 * 60 / Math.PI * 0.0820 * dr * ((omega2 - omega1) * Math.sin(phi) * Math.sin(delta)
 					+ Math.cos(phi) * Math.cos(delta) * (Math.sin(omega2) - Math.sin(omega1)));
 		}