From 01cdd3f0e1911ae39137150548c630bf09fa4059 Mon Sep 17 00:00:00 2001
From: Dave Parker <dave.x.parker@gmail.com>
Date: Mon, 23 Oct 2006 15:26:06 +0000
Subject: [PATCH] Optimisation to CTMC transient probability computation for
 when time is zero.

git-svn-id: https://www.prismmodelchecker.org/svn/prism/prism/trunk@73 bbc10eb1-c90d-0410-af57-cb519fbb1720
---
 prism/src/prism/StochModelChecker.java | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/prism/src/prism/StochModelChecker.java b/prism/src/prism/StochModelChecker.java
index edfdfd41..7a3a0f15 100644
--- a/prism/src/prism/StochModelChecker.java
+++ b/prism/src/prism/StochModelChecker.java
@@ -2023,7 +2023,13 @@ public class StochModelChecker implements ModelChecker
 		
 		// compute transient probabilities
 		try {
-			probs = computeTransientProbs(trans, init, time);
+			// special case: time = 0
+			if (time == 0.0) {
+				JDD.Ref(init);
+				probs = new StateProbsMTBDD(init, model);
+			} else {
+				probs = computeTransientProbs(trans, init, time);
+			}
 		}
 		catch (PrismException e) {
 			JDD.Deref(init);