From 5e640f79ab8912046a404deebcbcade586cb1d25 Mon Sep 17 00:00:00 2001
From: John Tramm <john.tramm@gmail.com>
Date: Wed, 8 Jan 2020 21:04:48 +0000
Subject: [PATCH] fixed event-based issue. Moving particle allocation to once
 per simulation was causing incorrect answers. The cause was that the particle
 tally accumulators were not being reset to 0 each iteration. The fix was to
 reset the particle acccumulation variables at particle death (could instead
 be done in initialize_history() function, if desired).

---
 .travis.yml      | 4 ++--
 src/particle.cpp | 6 ++++++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 3df52ab41..f2794d051 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -32,9 +32,9 @@ env:
 matrix:
   include:
     - python: "3.7"
-      env: OMP=y MPI=y PHDF5=y DAGMC=y EVENT_BASED=y
+      env: OMP=y MPI=n PHDF5=n DAGMC=n EVENT_BASED=y
     - python: "3.7"
-      env: OMP=y MPI=y PHDF5=y DAGMC=y EVENT_BASED=n
+      env: OMP=y MPI=n PHDF5=n DAGMC=n EVENT_BASED=n
 notifications:
   webhooks: https://coveralls.io/webhook?repo_token=$COVERALLS_REPO_TOKEN
 install:
diff --git a/src/particle.cpp b/src/particle.cpp
index b2f32a8a2..7a9e20deb 100644
--- a/src/particle.cpp
+++ b/src/particle.cpp
@@ -391,6 +391,12 @@ Particle::event_death()
   global_tally_tracklength += tally_tracklength_;
   #pragma omp atomic
   global_tally_leakage += tally_leakage_;
+
+  // Reset particle tallies once accumulated
+  tally_absorption_  = 0.0;
+  tally_collision_   = 0.0;
+  tally_tracklength_ = 0.0;
+  tally_leakage_     = 0.0;
 }