From f216ee3fb43da3a18062d90e00eb315f5c135416 Mon Sep 17 00:00:00 2001
From: Shikhar Kumar <shikhark@mit.edu>
Date: Tue, 2 Oct 2018 22:02:54 -0400
Subject: [PATCH] First pass at removing replay_batch_history

---
 src/simulation.F90  | 71 ++-------------------------------------------
 src/state_point.F90 | 16 +++++++++-
 2 files changed, 17 insertions(+), 70 deletions(-)

diff --git a/src/simulation.F90 b/src/simulation.F90
index f9fcc62bd5..b51962a17e 100644
--- a/src/simulation.F90
+++ b/src/simulation.F90
@@ -87,13 +87,6 @@ contains
 
     call initialize_batch()
 
-    ! Handle restart runs
-    if (restart_run .and. current_batch <= restart_batch) then
-      call replay_batch_history()
-      status = STATUS_EXIT_NORMAL
-      return
-    end if
-
     ! =======================================================================
     ! LOOP OVER GENERATIONS
     GENERATION_LOOP: do current_gen = 1, gen_per_batch
@@ -205,7 +198,7 @@ contains
     total_weight = ZERO
 
     if ((n_inactive > 0 .and. current_batch == 1) .or. &
-         (restart_run .and. restart_batch <= n_inactive .and. current_batch == restart_batch)) then
+         (restart_run .and. restart_batch < n_inactive .and. current_batch == restart_batch + 1)) then
       ! Turn on inactive timer
       call time_inactive % start()
     elseif (current_batch == n_inactive + 1) then
@@ -387,48 +380,6 @@ contains
 
   end subroutine finalize_batch
 
-!===============================================================================
-! REPLAY_BATCH_HISTORY displays keff and entropy for each generation within a
-! batch using data read from a state point file
-!===============================================================================
-
-  subroutine replay_batch_history
-
-    ! Write message at beginning
-    if (n_realizations == 0) then
-      call write_message("Replaying history from state point...", 6)
-    end if
-
-    if (run_mode == MODE_EIGENVALUE) then
-      do current_gen = 1, gen_per_batch
-        call calculate_average_keff()
-
-        ! print out batch keff
-        if (verbosity >= 7) then
-          if (current_gen < gen_per_batch) then
-            if (master) call print_generation()
-          else
-            if (master) call print_batch_keff()
-          end if
-        end if
-      end do
-    end if
-
-    ! Increment n_realizations if in active batches as would ordinarily be done in finalize_batch
-    if (current_batch > n_inactive) then
-      if (reduce_tallies) then
-        n_realizations = n_realizations + 1
-      else
-        n_realizations = n_realizations + n_procs
-      end if
-    end if
-
-    ! Write message at end
-    if (current_batch == restart_batch) then
-      call write_message("Resuming simulation...", 6)
-    end if
-
-  end subroutine replay_batch_history
 
 !===============================================================================
 ! INITIALIZE_SIMULATION
@@ -492,29 +443,11 @@ contains
     ! file
     if (restart_run) then
       call load_state_point()
+      call write_message("Resuming simulation...", 6)
     else
       call initialize_source()
     end if
 
-    ! In restart, set the batch to begin from in order to reproduce the correct
-    ! average keff (used in sampling the fission bank).  Use n_realizations from
-    ! the statepoint rather than n_inactive in case openmc_reset was called in
-    ! the previous run.
-    if (restart_run) then
-      if (reduce_tallies) then
-        current_batch = restart_batch - n_realizations
-      else
-        current_batch = restart_batch - n_realizations*n_procs
-      end if
-      ! If simulation restarted from inactive batch, decrement current_batch
-      ! by one to replay an additional batch so that keff is set before resuming
-      ! simulation
-      if (restart_batch <= n_inactive) then
-        current_batch = current_batch - 1
-      end if
-      n_realizations = 0
-    end if
-
     ! Display header
     if (master) then
       if (run_mode == MODE_FIXEDSOURCE) then
diff --git a/src/state_point.F90 b/src/state_point.F90
index 526066c529..91d0f10908 100644
--- a/src/state_point.F90
+++ b/src/state_point.F90
@@ -16,7 +16,7 @@ module state_point
   use bank_header,        only: Bank
   use cmfd_header
   use constants
-  use eigenvalue,         only: openmc_get_keff
+  use eigenvalue,         only: openmc_get_keff, k_sum
   use endf,               only: reaction_name
   use error,              only: fatal_error, warning, write_message
   use hdf5_interface
@@ -749,6 +749,20 @@ contains
     ! Read number of realizations for global tallies
     call read_dataset(n_realizations, file_id, "n_realizations", indep=.true.)
 
+    ! Set k_sum, keff, and current_batch based on whether restart file is part
+    ! of active cycle or inactive cycle
+    if (restart_batch > n_inactive) then
+      do i = n_inactive + 1, restart_batch
+        k_sum(1) = k_sum(1) + k_generation % data(i)
+        k_sum(2) = k_sum(2) + k_generation % data(i)**2
+      end do
+      n = gen_per_batch*n_realizations
+      keff = k_sum(1) / n
+    else
+      keff = k_generation % data(n)
+    end if
+    current_batch = restart_batch
+
     ! Check to make sure source bank is present
     if (path_source_point == path_state_point .and. .not. source_present) then
       call fatal_error("Source bank must be contained in statepoint restart &