From 00d9bd162fcd4c9381ea8ac90879d8da0d780035 Mon Sep 17 00:00:00 2001
From: Sascha Wunderlich <sascha.wunderlich@tu-dresden.de>
Date: Mon, 14 Nov 2016 15:41:36 +0100
Subject: [PATCH] accumulation: don't advance good tracks

---
 prism/src/explicit/AccumulationProduct.java | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/prism/src/explicit/AccumulationProduct.java b/prism/src/explicit/AccumulationProduct.java
index 6c0f2b9a..112ef195 100644
--- a/prism/src/explicit/AccumulationProduct.java
+++ b/prism/src/explicit/AccumulationProduct.java
@@ -133,14 +133,17 @@ public abstract class AccumulationProduct<M extends Model,Component> extends Pro
 				newGoodTracks.clear(trackNr);
 			} else if (oldTrack == null) {
 				newTrack = null;
+			} else if (oldGoodTracks.get(trackNr)) {
+				newTrack = null;
 			} else {
 				assert oldTrack != null;
 				newTrack = updateTrack(modelFromStateId, oldTrack, accexp, weights, mc);
 			}
 			
 			// check whether the track is good
-			if(!newGoodTracks.get(trackNr)) {
-				newGoodTracks.set(trackNr, isGoodTrack(newTrack, accexp, mc));
+			if(oldGoodTracks.get(trackNr) || isGoodTrack(newTrack,accexp,mc)) {
+				newGoodTracks.set(trackNr);
+				newTrack = null;
 			}
 			
 			newTracks.add(newTrack);