From aa3e810729bdd5d69cb40c7a7529eaf86c32aa86 Mon Sep 17 00:00:00 2001
From: David A Minton <daminton@purdue.edu>
Date: Mon, 2 Aug 2021 19:08:49 -0400
Subject: [PATCH] Removed the mergesub_list call from inside the symba step

---
 src/symba/symba_collision.f90 | 5 -----
 src/symba/symba_discard.f90   | 8 +++++++-
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/symba/symba_collision.f90 b/src/symba/symba_collision.f90
index ed2e1e0a1..2614a486a 100644
--- a/src/symba/symba_collision.f90
+++ b/src/symba/symba_collision.f90
@@ -63,15 +63,10 @@ module subroutine symba_collision_check_plplenc(self, system, param, t, dt, irec
                   ! Check to see if either of these bodies has been involved with a collision before, and if so, make this a collisional family
                   if (pl%lcollision(ind1(k)) .or. pl%lcollision(ind2(k))) call pl%make_family([ind1(k),ind2(k)])
 
-                  ! Add any of the bodies that have *not* previously been involved in a collision to the subtraction list
-                  lmask(:) = .false.
-                  lmask(ind1(k)) = .not.pl%lcollision(ind1(k))
-                  lmask(ind2(k)) = .not.pl%lcollision(ind2(k))
                   ! Set the collision flag for these to bodies to true in case they become involved in another collision later in the step
                   pl%lcollision([ind1(k), ind2(k)]) = .true.
                   pl%lcollision([ind1(k), ind2(k)]) = .true.
                   pl%status([ind1(k), ind2(k)]) = COLLISION
-                  call system%mergesub_list%append(pl, lmask)
                end do
 
             end if
diff --git a/src/symba/symba_discard.f90 b/src/symba/symba_discard.f90
index 9a90d7ea1..f9066fdc6 100644
--- a/src/symba/symba_discard.f90
+++ b/src/symba/symba_discard.f90
@@ -37,7 +37,10 @@ end subroutine symba_discard_pl
    subroutine symba_discard_cb_pl(pl, system, param)
       !! author: David A. Minton
       !!
-      !!  Check to see if planets should be discarded based on their positions relative to the central body 
+      !! Check to see if planets should be discarded based on their positions relative to the central body.
+      !! If a body gets flagged here when it has also been previously flagged for a collision with another massive body,
+      !! its collisional status will be revoked. Discards due to colliding with or escaping the central body take precedence 
+      !! over pl-pl collisions
       !!
       !! Adapted from David E. Kaufmann's Swifter routine: symba_discard_cb.f90
       !! Adapted from Hal Levison's Swift routine discard_massive5.f
@@ -60,10 +63,12 @@ subroutine symba_discard_cb_pl(pl, system, param)
                rh2 = dot_product(pl%xh(:,i), pl%xh(:,i))
                if ((param%rmax >= 0.0_DP) .and. (rh2 > rmax2)) then
                   pl%ldiscard(i) = .true.
+                  pl%lcollision(i) = .false. 
                   pl%status(i) = DISCARDED_RMAX
                   write(*, *) "Massive body ",  pl%id(i), " too far from the central body at t = ", param%t
                else if ((param%rmin >= 0.0_DP) .and. (rh2 < rmin2)) then
                   pl%ldiscard(i) = .true.
+                  pl%lcollision(i) = .false. 
                   pl%status(i) = DISCARDED_RMIN
                   write(*, *) "Massive body ", pl%id(i), " too close to the central body at t = ", param%t
                else if (param%rmaxu >= 0.0_DP) then
@@ -72,6 +77,7 @@ subroutine symba_discard_cb_pl(pl, system, param)
                   energy = 0.5_DP * vb2 - system%msys / sqrt(rb2)
                   if ((energy > 0.0_DP) .and. (rb2 > rmaxu2)) then
                      pl%ldiscard(i) = .true.
+                     pl%lcollision(i) = .false. 
                      pl%status(i) = DISCARDED_RMAXU
                      write(*, *) "Massive body ", pl%id(i), " is unbound and too far from barycenter at t = ", param%t
                   end if