From 2f4b841d38a365500366177c520a53d1df7ebc90 Mon Sep 17 00:00:00 2001
From: Tiger Lu <tigerlu@Tigers-MBP-2.stdusr.yale.internal>
Date: Thu, 25 Jan 2024 16:54:21 -0500
Subject: [PATCH] fixes collision test

---
 src/integrator_trace.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/src/integrator_trace.c b/src/integrator_trace.c
index 239db2d59..d0cd76731 100644
--- a/src/integrator_trace.c
+++ b/src/integrator_trace.c
@@ -351,26 +351,28 @@ void reb_integrator_trace_bs_step(struct reb_simulation* const r, double dt){
     // run
     const double old_dt = r->dt;
     const double old_t = r->t;
-    double t = r->t;
+    //double t = r->t;
     const double t_needed = r->t + dt;
     reb_integrator_bs_reset(r);
 
     struct reb_ode* nbody_ode = reb_ode_create(r, ri_trace->encounter_N*3*2);
     nbody_ode->derivatives = reb_integrator_trace_nbody_derivatives;
     nbody_ode->needs_nbody = 0;
-    double* const y = nbody_ode->y;
+    double* y;
 
-    while(t < t_needed && fabs(dt/old_dt)>1e-14 ){
+    while(r->t < t_needed && fabs(dt/old_dt)>1e-14 ){
+        y = nbody_ode->y;
+        
         // In case of overshoot
-        if (t + dt >  t_needed){
-            dt = t_needed - t;
+        if (r->t + dt >  t_needed){
+            dt = t_needed - r->t;
         }
 
         struct reb_particle star = r->particles[0]; // backup velocity
         r->particles[0].vx = 0; // star does not move in dh
         r->particles[0].vy = 0;
         r->particles[0].vz = 0;
-        
+
         for (unsigned int i=0; i<ri_trace->encounter_N; i++){
             const int mi = ri_trace->encounter_map[i];
             const struct reb_particle p = r->particles[mi];
@@ -384,11 +386,11 @@ void reb_integrator_trace_bs_step(struct reb_simulation* const r, double dt){
 
         int success = reb_integrator_bs_step(r, dt);
         if (success){
-            t += dt;
+            r->t += dt;
         }
         dt = r->ri_bs.dt_proposed;
         reb_integrator_trace_update_particles(r, nbody_ode->y);
-        
+
         r->particles[0].vx = star.vx; // restore every timestep for collisions
         r->particles[0].vy = star.vy;
         r->particles[0].vz = star.vz;
@@ -430,7 +432,7 @@ void reb_integrator_trace_bs_step(struct reb_simulation* const r, double dt){
             r->particles[mi] = ri_trace->particles_backup_kepler[mi];
         }
     }
-    
+
     reb_ode_free(nbody_ode);
 
     r->t = old_t;
@@ -630,8 +632,8 @@ void reb_integrator_trace_part2(struct reb_simulation* const r){
 
     reb_integrator_trace_interaction_step(r, r->dt/2.);
     reb_integrator_trace_jump_step(r, r->dt/2.);
-    reb_integrator_trace_kepler_step(r, r->dt); // always accept this
     reb_integrator_trace_com_step(r,r->dt);
+    reb_integrator_trace_kepler_step(r, r->dt); // always accept this
     reb_integrator_trace_jump_step(r, r->dt/2.);
     reb_integrator_trace_interaction_step(r, r->dt/2.);