From 2e06f9391157b2d87cf2798b9cbe0027621898e2 Mon Sep 17 00:00:00 2001
From: David A Minton <daminton@purdue.edu>
Date: Sat, 31 Jul 2021 06:57:05 -0400
Subject: [PATCH] Started adding collisional family code for pl-pl mergers
 before they shut down the clusters for maintenence

---
 .../swiftest_vs_swifter.ipynb                 | 483 +++++++++++++++++-
 src/symba/symba_collision.f90                 |  50 +-
 2 files changed, 505 insertions(+), 28 deletions(-)

diff --git a/examples/symba_swifter_comparison/1pl_1pl_encounter/swiftest_vs_swifter.ipynb b/examples/symba_swifter_comparison/1pl_1pl_encounter/swiftest_vs_swifter.ipynb
index 57dd1934a..34c978f58 100644
--- a/examples/symba_swifter_comparison/1pl_1pl_encounter/swiftest_vs_swifter.ipynb
+++ b/examples/symba_swifter_comparison/1pl_1pl_encounter/swiftest_vs_swifter.ipynb
@@ -21,9 +21,9 @@
      "output_type": "stream",
      "text": [
       "Reading Swifter file param.swifter.in\n",
-      "Reading in time 6.845e-04\n",
+      "Reading in time 1.506e-01\n",
       "Creating Dataset\n",
-      "Successfully converted 2 output frames.\n",
+      "Successfully converted 221 output frames.\n",
       "Swifter simulation data stored as xarray DataSet .ds\n"
      ]
     }
@@ -44,25 +44,9 @@
      "text": [
       "Reading Swiftest file param.swiftest.in\n",
       "Reading in time 1.506e-01\n",
-      "Creating Dataset\n"
-     ]
-    },
-    {
-     "ename": "MergeError",
-     "evalue": "conflicting values for variable 'Mass' on objects to be combined. You can skip this check by specifying compat='override'.",
-     "output_type": "error",
-     "traceback": [
-      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
-      "\u001b[0;31mMergeError\u001b[0m                                Traceback (most recent call last)",
-      "\u001b[0;32m<ipython-input-3-0c277090153d>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[1;32m      1\u001b[0m \u001b[0mswiftestsim\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mswiftest\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mSimulation\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mparam_file\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0;34m\"param.swiftest.in\"\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 2\u001b[0;31m \u001b[0mswiftestsim\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mbin2xr\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
-      "\u001b[0;32m~/git/swiftest/python/swiftest/swiftest/simulation_class.py\u001b[0m in \u001b[0;36mbin2xr\u001b[0;34m(self)\u001b[0m\n\u001b[1;32m    135\u001b[0m     \u001b[0;32mdef\u001b[0m \u001b[0mbin2xr\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    136\u001b[0m         \u001b[0;32mif\u001b[0m \u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mcodename\u001b[0m \u001b[0;34m==\u001b[0m \u001b[0;34m\"Swiftest\"\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 137\u001b[0;31m             \u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mds\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mio\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mswiftest2xr\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mparam\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    138\u001b[0m             \u001b[0mprint\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m'Swiftest simulation data stored as xarray DataSet .ds'\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    139\u001b[0m         \u001b[0;32melif\u001b[0m \u001b[0mself\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mcodename\u001b[0m \u001b[0;34m==\u001b[0m \u001b[0;34m\"Swifter\"\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
-      "\u001b[0;32m~/git/swiftest/python/swiftest/swiftest/io.py\u001b[0m in \u001b[0;36mswiftest2xr\u001b[0;34m(param)\u001b[0m\n\u001b[1;32m    632\u001b[0m     \u001b[0mtpds\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mtpda\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mto_dataset\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mdim\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0;34m'vec'\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    633\u001b[0m     \u001b[0mprint\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m'\\nCreating Dataset'\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 634\u001b[0;31m     \u001b[0mds\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mxr\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mcombine_by_coords\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0mcbds\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mplds\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mtpds\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    635\u001b[0m     \u001b[0mprint\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34mf\"Successfully converted {ds.sizes['time']} output frames.\"\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    636\u001b[0m     \u001b[0;32mreturn\u001b[0m \u001b[0mds\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
-      "\u001b[0;32m~/.conda/envs/cent7/2020.02-py37/swiftestOOF/lib/python3.7/site-packages/xarray/core/combine.py\u001b[0m in \u001b[0;36mcombine_by_coords\u001b[0;34m(datasets, compat, data_vars, coords, fill_value, join, combine_attrs)\u001b[0m\n\u001b[1;32m    816\u001b[0m         \u001b[0mfill_value\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0mfill_value\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    817\u001b[0m         \u001b[0mjoin\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0mjoin\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 818\u001b[0;31m         \u001b[0mcombine_attrs\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0mcombine_attrs\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    819\u001b[0m     )\n",
-      "\u001b[0;32m~/.conda/envs/cent7/2020.02-py37/swiftestOOF/lib/python3.7/site-packages/xarray/core/merge.py\u001b[0m in \u001b[0;36mmerge\u001b[0;34m(objects, compat, join, fill_value, combine_attrs)\u001b[0m\n\u001b[1;32m    893\u001b[0m         \u001b[0mjoin\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    894\u001b[0m         \u001b[0mcombine_attrs\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0mcombine_attrs\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 895\u001b[0;31m         \u001b[0mfill_value\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0mfill_value\u001b[0m\u001b[0;34m,\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    896\u001b[0m     )\n\u001b[1;32m    897\u001b[0m     \u001b[0mmerged\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0mDataset\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0m_construct_direct\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m**\u001b[0m\u001b[0mmerge_result\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0m_asdict\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
-      "\u001b[0;32m~/.conda/envs/cent7/2020.02-py37/swiftestOOF/lib/python3.7/site-packages/xarray/core/merge.py\u001b[0m in \u001b[0;36mmerge_core\u001b[0;34m(objects, compat, join, combine_attrs, priority_arg, explicit_coords, indexes, fill_value)\u001b[0m\n\u001b[1;32m    625\u001b[0m     \u001b[0mprioritized\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0m_get_priority_vars_and_indexes\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0maligned\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mpriority_arg\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mcompat\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0mcompat\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    626\u001b[0m     variables, out_indexes = merge_collected(\n\u001b[0;32m--> 627\u001b[0;31m         \u001b[0mcollected\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mprioritized\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mcompat\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0mcompat\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mcombine_attrs\u001b[0m\u001b[0;34m=\u001b[0m\u001b[0mcombine_attrs\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    628\u001b[0m     )\n\u001b[1;32m    629\u001b[0m     \u001b[0massert_unique_multiindex_level_names\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mvariables\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
-      "\u001b[0;32m~/.conda/envs/cent7/2020.02-py37/swiftestOOF/lib/python3.7/site-packages/xarray/core/merge.py\u001b[0m in \u001b[0;36mmerge_collected\u001b[0;34m(grouped, prioritized, compat, combine_attrs)\u001b[0m\n\u001b[1;32m    232\u001b[0m                 \u001b[0mvariables\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0;34m[\u001b[0m\u001b[0mvariable\u001b[0m \u001b[0;32mfor\u001b[0m \u001b[0mvariable\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0m_\u001b[0m \u001b[0;32min\u001b[0m \u001b[0melements_list\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    233\u001b[0m                 \u001b[0;32mtry\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m--> 234\u001b[0;31m                     \u001b[0mmerged_vars\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0mname\u001b[0m\u001b[0;34m]\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0munique_variable\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mname\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mvariables\u001b[0m\u001b[0;34m,\u001b[0m \u001b[0mcompat\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    235\u001b[0m                 \u001b[0;32mexcept\u001b[0m \u001b[0mMergeError\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    236\u001b[0m                     \u001b[0;32mif\u001b[0m \u001b[0mcompat\u001b[0m \u001b[0;34m!=\u001b[0m \u001b[0;34m\"minimal\"\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
-      "\u001b[0;32m~/.conda/envs/cent7/2020.02-py37/swiftestOOF/lib/python3.7/site-packages/xarray/core/merge.py\u001b[0m in \u001b[0;36munique_variable\u001b[0;34m(name, variables, compat, equals)\u001b[0m\n\u001b[1;32m    140\u001b[0m     \u001b[0;32mif\u001b[0m \u001b[0;32mnot\u001b[0m \u001b[0mequals\u001b[0m\u001b[0;34m:\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    141\u001b[0m         raise MergeError(\n\u001b[0;32m--> 142\u001b[0;31m             \u001b[0;34mf\"conflicting values for variable {name!r} on objects to be combined. \"\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m    143\u001b[0m             \u001b[0;34m\"You can skip this check by specifying compat='override'.\"\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m    144\u001b[0m         )\n",
-      "\u001b[0;31mMergeError\u001b[0m: conflicting values for variable 'Mass' on objects to be combined. You can skip this check by specifying compat='override'."
+      "Creating Dataset\n",
+      "Successfully converted 221 output frames.\n",
+      "Swiftest simulation data stored as xarray DataSet .ds\n"
      ]
     }
    ],
@@ -73,7 +57,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 4,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -82,7 +66,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 5,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -91,18 +75,463 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 6,
    "metadata": {},
-   "outputs": [],
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "[<matplotlib.lines.Line2D at 0x2ab850525310>,\n",
+       " <matplotlib.lines.Line2D at 0x2ab85052d090>]"
+      ]
+     },
+     "execution_count": 6,
+     "metadata": {},
+     "output_type": "execute_result"
+    },
+    {
+     "data": {
+      "image/png": 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\n",
+      "text/plain": [
+       "<Figure size 432x288 with 1 Axes>"
+      ]
+     },
+     "metadata": {
+      "needs_background": "light"
+     },
+     "output_type": "display_data"
+    }
+   ],
    "source": [
     "swiftdiff['vx'].plot.line(x=\"time (y)\")"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 7,
    "metadata": {},
-   "outputs": [],
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
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+       "<defs>\n",
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+       "</defs>\n",
+       "</svg>\n",
+       "<style>/* CSS stylesheet for displaying xarray objects in jupyterlab.\n",
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+       "  --xr-background-color: var(--jp-layout-color0, white);\n",
+       "  --xr-background-color-row-even: var(--jp-layout-color1, white);\n",
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+       "\n",
+       "html[theme=dark],\n",
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+       "  --xr-font-color2: rgba(255, 255, 255, 0.54);\n",
+       "  --xr-font-color3: rgba(255, 255, 255, 0.38);\n",
+       "  --xr-border-color: #1F1F1F;\n",
+       "  --xr-disabled-color: #515151;\n",
+       "  --xr-background-color: #111111;\n",
+       "  --xr-background-color-row-even: #111111;\n",
+       "  --xr-background-color-row-odd: #313131;\n",
+       "}\n",
+       "\n",
+       ".xr-wrap {\n",
+       "  display: block;\n",
+       "  min-width: 300px;\n",
+       "  max-width: 700px;\n",
+       "}\n",
+       "\n",
+       ".xr-text-repr-fallback {\n",
+       "  /* fallback to plain text repr when CSS is not injected (untrusted notebook) */\n",
+       "  display: none;\n",
+       "}\n",
+       "\n",
+       ".xr-header {\n",
+       "  padding-top: 6px;\n",
+       "  padding-bottom: 6px;\n",
+       "  margin-bottom: 4px;\n",
+       "  border-bottom: solid 1px var(--xr-border-color);\n",
+       "}\n",
+       "\n",
+       ".xr-header > div,\n",
+       ".xr-header > ul {\n",
+       "  display: inline;\n",
+       "  margin-top: 0;\n",
+       "  margin-bottom: 0;\n",
+       "}\n",
+       "\n",
+       ".xr-obj-type,\n",
+       ".xr-array-name {\n",
+       "  margin-left: 2px;\n",
+       "  margin-right: 10px;\n",
+       "}\n",
+       "\n",
+       ".xr-obj-type {\n",
+       "  color: var(--xr-font-color2);\n",
+       "}\n",
+       "\n",
+       ".xr-sections {\n",
+       "  padding-left: 0 !important;\n",
+       "  display: grid;\n",
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+       "\n",
+       ".xr-section-item {\n",
+       "  display: contents;\n",
+       "}\n",
+       "\n",
+       ".xr-section-item input {\n",
+       "  display: none;\n",
+       "}\n",
+       "\n",
+       ".xr-section-item input + label {\n",
+       "  color: var(--xr-disabled-color);\n",
+       "}\n",
+       "\n",
+       ".xr-section-item input:enabled + label {\n",
+       "  cursor: pointer;\n",
+       "  color: var(--xr-font-color2);\n",
+       "}\n",
+       "\n",
+       ".xr-section-item input:enabled + label:hover {\n",
+       "  color: var(--xr-font-color0);\n",
+       "}\n",
+       "\n",
+       ".xr-section-summary {\n",
+       "  grid-column: 1;\n",
+       "  color: var(--xr-font-color2);\n",
+       "  font-weight: 500;\n",
+       "}\n",
+       "\n",
+       ".xr-section-summary > span {\n",
+       "  display: inline-block;\n",
+       "  padding-left: 0.5em;\n",
+       "}\n",
+       "\n",
+       ".xr-section-summary-in:disabled + label {\n",
+       "  color: var(--xr-font-color2);\n",
+       "}\n",
+       "\n",
+       ".xr-section-summary-in + label:before {\n",
+       "  display: inline-block;\n",
+       "  content: '►';\n",
+       "  font-size: 11px;\n",
+       "  width: 15px;\n",
+       "  text-align: center;\n",
+       "}\n",
+       "\n",
+       ".xr-section-summary-in:disabled + label:before {\n",
+       "  color: var(--xr-disabled-color);\n",
+       "}\n",
+       "\n",
+       ".xr-section-summary-in:checked + label:before {\n",
+       "  content: '▼';\n",
+       "}\n",
+       "\n",
+       ".xr-section-summary-in:checked + label > span {\n",
+       "  display: none;\n",
+       "}\n",
+       "\n",
+       ".xr-section-summary,\n",
+       ".xr-section-inline-details {\n",
+       "  padding-top: 4px;\n",
+       "  padding-bottom: 4px;\n",
+       "}\n",
+       "\n",
+       ".xr-section-inline-details {\n",
+       "  grid-column: 2 / -1;\n",
+       "}\n",
+       "\n",
+       ".xr-section-details {\n",
+       "  display: none;\n",
+       "  grid-column: 1 / -1;\n",
+       "  margin-bottom: 5px;\n",
+       "}\n",
+       "\n",
+       ".xr-section-summary-in:checked ~ .xr-section-details {\n",
+       "  display: contents;\n",
+       "}\n",
+       "\n",
+       ".xr-array-wrap {\n",
+       "  grid-column: 1 / -1;\n",
+       "  display: grid;\n",
+       "  grid-template-columns: 20px auto;\n",
+       "}\n",
+       "\n",
+       ".xr-array-wrap > label {\n",
+       "  grid-column: 1;\n",
+       "  vertical-align: top;\n",
+       "}\n",
+       "\n",
+       ".xr-preview {\n",
+       "  color: var(--xr-font-color3);\n",
+       "}\n",
+       "\n",
+       ".xr-array-preview,\n",
+       ".xr-array-data {\n",
+       "  padding: 0 5px !important;\n",
+       "  grid-column: 2;\n",
+       "}\n",
+       "\n",
+       ".xr-array-data,\n",
+       ".xr-array-in:checked ~ .xr-array-preview {\n",
+       "  display: none;\n",
+       "}\n",
+       "\n",
+       ".xr-array-in:checked ~ .xr-array-data,\n",
+       ".xr-array-preview {\n",
+       "  display: inline-block;\n",
+       "}\n",
+       "\n",
+       ".xr-dim-list {\n",
+       "  display: inline-block !important;\n",
+       "  list-style: none;\n",
+       "  padding: 0 !important;\n",
+       "  margin: 0;\n",
+       "}\n",
+       "\n",
+       ".xr-dim-list li {\n",
+       "  display: inline-block;\n",
+       "  padding: 0;\n",
+       "  margin: 0;\n",
+       "}\n",
+       "\n",
+       ".xr-dim-list:before {\n",
+       "  content: '(';\n",
+       "}\n",
+       "\n",
+       ".xr-dim-list:after {\n",
+       "  content: ')';\n",
+       "}\n",
+       "\n",
+       ".xr-dim-list li:not(:last-child):after {\n",
+       "  content: ',';\n",
+       "  padding-right: 5px;\n",
+       "}\n",
+       "\n",
+       ".xr-has-index {\n",
+       "  font-weight: bold;\n",
+       "}\n",
+       "\n",
+       ".xr-var-list,\n",
+       ".xr-var-item {\n",
+       "  display: contents;\n",
+       "}\n",
+       "\n",
+       ".xr-var-item > div,\n",
+       ".xr-var-item label,\n",
+       ".xr-var-item > .xr-var-name span {\n",
+       "  background-color: var(--xr-background-color-row-even);\n",
+       "  margin-bottom: 0;\n",
+       "}\n",
+       "\n",
+       ".xr-var-item > .xr-var-name:hover span {\n",
+       "  padding-right: 5px;\n",
+       "}\n",
+       "\n",
+       ".xr-var-list > li:nth-child(odd) > div,\n",
+       ".xr-var-list > li:nth-child(odd) > label,\n",
+       ".xr-var-list > li:nth-child(odd) > .xr-var-name span {\n",
+       "  background-color: var(--xr-background-color-row-odd);\n",
+       "}\n",
+       "\n",
+       ".xr-var-name {\n",
+       "  grid-column: 1;\n",
+       "}\n",
+       "\n",
+       ".xr-var-dims {\n",
+       "  grid-column: 2;\n",
+       "}\n",
+       "\n",
+       ".xr-var-dtype {\n",
+       "  grid-column: 3;\n",
+       "  text-align: right;\n",
+       "  color: var(--xr-font-color2);\n",
+       "}\n",
+       "\n",
+       ".xr-var-preview {\n",
+       "  grid-column: 4;\n",
+       "}\n",
+       "\n",
+       ".xr-var-name,\n",
+       ".xr-var-dims,\n",
+       ".xr-var-dtype,\n",
+       ".xr-preview,\n",
+       ".xr-attrs dt {\n",
+       "  white-space: nowrap;\n",
+       "  overflow: hidden;\n",
+       "  text-overflow: ellipsis;\n",
+       "  padding-right: 10px;\n",
+       "}\n",
+       "\n",
+       ".xr-var-name:hover,\n",
+       ".xr-var-dims:hover,\n",
+       ".xr-var-dtype:hover,\n",
+       ".xr-attrs dt:hover {\n",
+       "  overflow: visible;\n",
+       "  width: auto;\n",
+       "  z-index: 1;\n",
+       "}\n",
+       "\n",
+       ".xr-var-attrs,\n",
+       ".xr-var-data {\n",
+       "  display: none;\n",
+       "  background-color: var(--xr-background-color) !important;\n",
+       "  padding-bottom: 5px !important;\n",
+       "}\n",
+       "\n",
+       ".xr-var-attrs-in:checked ~ .xr-var-attrs,\n",
+       ".xr-var-data-in:checked ~ .xr-var-data {\n",
+       "  display: block;\n",
+       "}\n",
+       "\n",
+       ".xr-var-data > table {\n",
+       "  float: right;\n",
+       "}\n",
+       "\n",
+       ".xr-var-name span,\n",
+       ".xr-var-data,\n",
+       ".xr-attrs {\n",
+       "  padding-left: 25px !important;\n",
+       "}\n",
+       "\n",
+       ".xr-attrs,\n",
+       ".xr-var-attrs,\n",
+       ".xr-var-data {\n",
+       "  grid-column: 1 / -1;\n",
+       "}\n",
+       "\n",
+       "dl.xr-attrs {\n",
+       "  padding: 0;\n",
+       "  margin: 0;\n",
+       "  display: grid;\n",
+       "  grid-template-columns: 125px auto;\n",
+       "}\n",
+       "\n",
+       ".xr-attrs dt,\n",
+       ".xr-attrs dd {\n",
+       "  padding: 0;\n",
+       "  margin: 0;\n",
+       "  float: left;\n",
+       "  padding-right: 10px;\n",
+       "  width: auto;\n",
+       "}\n",
+       "\n",
+       ".xr-attrs dt {\n",
+       "  font-weight: normal;\n",
+       "  grid-column: 1;\n",
+       "}\n",
+       "\n",
+       ".xr-attrs dt:hover span {\n",
+       "  display: inline-block;\n",
+       "  background: var(--xr-background-color);\n",
+       "  padding-right: 10px;\n",
+       "}\n",
+       "\n",
+       ".xr-attrs dd {\n",
+       "  grid-column: 2;\n",
+       "  white-space: pre-wrap;\n",
+       "  word-break: break-all;\n",
+       "}\n",
+       "\n",
+       ".xr-icon-database,\n",
+       ".xr-icon-file-text2 {\n",
+       "  display: inline-block;\n",
+       "  vertical-align: middle;\n",
+       "  width: 1em;\n",
+       "  height: 1.5em !important;\n",
+       "  stroke-width: 0;\n",
+       "  stroke: currentColor;\n",
+       "  fill: currentColor;\n",
+       "}\n",
+       "</style><pre class='xr-text-repr-fallback'>&lt;xarray.DataArray &#x27;vx&#x27; (time (y): 221)&gt;\n",
+       "array([ 0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0., nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan,\n",
+       "       nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan])\n",
+       "Coordinates:\n",
+       "    id        float64 100.0\n",
+       "  * time (y)  (time (y)) float64 0.0 0.0006845 0.001369 ... 0.1492 0.1499 0.1506</pre><div class='xr-wrap' hidden><div class='xr-header'><div class='xr-obj-type'>xarray.DataArray</div><div class='xr-array-name'>'vx'</div><ul class='xr-dim-list'><li><span class='xr-has-index'>time (y)</span>: 221</li></ul></div><ul class='xr-sections'><li class='xr-section-item'><div class='xr-array-wrap'><input id='section-459e135a-7287-42da-b8ae-9a0dbf03188e' class='xr-array-in' type='checkbox' checked><label for='section-459e135a-7287-42da-b8ae-9a0dbf03188e' title='Show/hide data repr'><svg class='icon xr-icon-database'><use xlink:href='#icon-database'></use></svg></label><div class='xr-array-preview xr-preview'><span>0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 ... nan nan nan nan nan nan nan nan</span></div><div class='xr-array-data'><pre>array([ 0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0., nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan,\n",
+       "       nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan])</pre></div></div></li><li class='xr-section-item'><input id='section-303d42b0-335e-41ac-8a6c-7f1fc862c2d5' class='xr-section-summary-in' type='checkbox'  checked><label for='section-303d42b0-335e-41ac-8a6c-7f1fc862c2d5' class='xr-section-summary' >Coordinates: <span>(2)</span></label><div class='xr-section-inline-details'></div><div class='xr-section-details'><ul class='xr-var-list'><li class='xr-var-item'><div class='xr-var-name'><span>id</span></div><div class='xr-var-dims'>()</div><div class='xr-var-dtype'>float64</div><div class='xr-var-preview xr-preview'>100.0</div><input id='attrs-3a547b3c-851a-4a9b-89d9-85fd5cb6b01b' class='xr-var-attrs-in' type='checkbox' disabled><label for='attrs-3a547b3c-851a-4a9b-89d9-85fd5cb6b01b' title='Show/Hide attributes'><svg class='icon xr-icon-file-text2'><use xlink:href='#icon-file-text2'></use></svg></label><input id='data-91b3bcb0-e16b-4f77-b98d-404d2b9f249e' class='xr-var-data-in' type='checkbox'><label for='data-91b3bcb0-e16b-4f77-b98d-404d2b9f249e' title='Show/Hide data repr'><svg class='icon xr-icon-database'><use xlink:href='#icon-database'></use></svg></label><div class='xr-var-attrs'><dl class='xr-attrs'></dl></div><div class='xr-var-data'><pre>array(100.)</pre></div></li><li class='xr-var-item'><div class='xr-var-name'><span class='xr-has-index'>time (y)</span></div><div class='xr-var-dims'>(time (y))</div><div class='xr-var-dtype'>float64</div><div class='xr-var-preview xr-preview'>0.0 0.0006845 ... 0.1499 0.1506</div><input id='attrs-c314fd4c-dd70-4fd1-ad93-5db95038eb61' class='xr-var-attrs-in' type='checkbox' disabled><label for='attrs-c314fd4c-dd70-4fd1-ad93-5db95038eb61' title='Show/Hide attributes'><svg class='icon xr-icon-file-text2'><use xlink:href='#icon-file-text2'></use></svg></label><input id='data-4a90fcbd-5eac-41ca-9a71-1e0f281c9638' class='xr-var-data-in' type='checkbox'><label for='data-4a90fcbd-5eac-41ca-9a71-1e0f281c9638' title='Show/Hide data repr'><svg class='icon xr-icon-database'><use xlink:href='#icon-database'></use></svg></label><div class='xr-var-attrs'><dl class='xr-attrs'></dl></div><div class='xr-var-data'><pre>array([0.      , 0.000684, 0.001369, ..., 0.149213, 0.149897, 0.150582])</pre></div></li></ul></div></li><li class='xr-section-item'><input id='section-6ff92457-942d-4f8c-9bb1-2ab62024f19a' class='xr-section-summary-in' type='checkbox' disabled ><label for='section-6ff92457-942d-4f8c-9bb1-2ab62024f19a' class='xr-section-summary'  title='Expand/collapse section'>Attributes: <span>(0)</span></label><div class='xr-section-inline-details'></div><div class='xr-section-details'><dl class='xr-attrs'></dl></div></li></ul></div></div>"
+      ],
+      "text/plain": [
+       "<xarray.DataArray 'vx' (time (y): 221)>\n",
+       "array([ 0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,\n",
+       "        0.,  0., nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan,\n",
+       "       nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan, nan])\n",
+       "Coordinates:\n",
+       "    id        float64 100.0\n",
+       "  * time (y)  (time (y)) float64 0.0 0.0006845 0.001369 ... 0.1492 0.1499 0.1506"
+      ]
+     },
+     "execution_count": 7,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
    "source": [
     "swiftdiff['vx'].sel(id=100)"
    ]
diff --git a/src/symba/symba_collision.f90 b/src/symba/symba_collision.f90
index 2eaa521ee..bdf83a595 100644
--- a/src/symba/symba_collision.f90
+++ b/src/symba/symba_collision.f90
@@ -19,6 +19,54 @@ module subroutine symba_collision_check_plplenc(self, system, param, t, dt, irec
       real(DP),                   intent(in)    :: t      !! current time
       real(DP),                   intent(in)    :: dt     !! step size
       integer(I4B),               intent(in)    :: irec   !! Current recursion level
+      ! Internals
+      logical, dimension(:), allocatable        :: lcollision, lmask
+      real(DP), dimension(NDIM)                 :: xr, vr
+      integer(I4B)                              :: k
+      real(DP)                                  :: rlim, mtot
+
+      if (self%nenc == 0) return
+
+      select type(pl => system%pl)
+      class is (symba_pl)
+         select type(tp => system%tp)
+         class is (symba_tp)
+            associate(plplenc_list => self, nplplenc => self%nenc, ind1 => self%index1, ind2 => self%index2)
+               allocate(lmask(nplplenc))
+               lmask(:) = ((plplenc_list%status(1:nplplenc) == ACTIVE) &
+                     .and. (pl%levelg(ind1(1:nplplenc)) >= irec) &
+                     .and. (pl%levelg(ind2(1:nplplenc)) >= irec))
+               if (.not.any(lmask(:))) return
+
+               allocate(lcollision(nplplenc))
+               lcollision(:) = .false.
+
+               do concurrent(k = 1:nplplenc, lmask(k))
+                  xr(:) = pl%xh(:, ind1(k)) - pl%xh(:, ind2(k)) 
+                  vr(:) = pl%vb(:, ind1(k)) - pl%vb(:, ind2(k))
+                  rlim = pl%radius(ind1(k)) + pl%radius(ind2(k))
+                  mtot = pl%Gmass(ind1(k)) + pl%Gmass(ind2(k))
+                  lcollision(k) = symba_collision_check_one(xr(1), xr(2), xr(3), vr(1), vr(2), vr(3), mtot, rlim, dt, plplenc_list%lvdotr(k))
+               end do
+
+               if (any(lcollision(:))) then
+                  do k = 1, nplplenc
+                     if (plplenc_list%status(k) /= COLLISION) cycle
+                     plplenc_list%status(k) = COLLISION
+                     plplenc_list%xh1(:,k) = pl%xh(:,ind1(k)) 
+                     plplenc_list%vb1(:,k) = pl%vb(:,ind1(k)) 
+                     plplenc_list%xh2(:,k) = pl%xh(:,ind2(k))
+                     plplenc_list%vb2(:,k) = pl%vb(:,ind2(k))
+                     if (pl%lcollision(ind1(k)) .or. pl%lcollision(ind2(k))) call plplenc_list%make_family(system)
+                     pl%lcollision(ind1(k)) = .true.
+                     pl%lcollision(ind2(k)) = .true.
+                  end do
+               end if
+            end associate
+         end select
+      end select
+
+      return 
 
       return
    end subroutine symba_collision_check_plplenc
@@ -51,7 +99,7 @@ module subroutine symba_collision_check_pltpenc(self, system, param, t, dt, irec
       class is (symba_pl)
          select type(tp => system%tp)
          class is (symba_tp)
-            associate(pltpenc_list => self, npltpenc => self%nenc, plind => self%index1, tpind => self%index2 )
+            associate(pltpenc_list => self, npltpenc => self%nenc, plind => self%index1, tpind => self%index2)
                allocate(lmask(npltpenc))
                lmask(:) = ((pltpenc_list%status(1:npltpenc) == ACTIVE) &
                      .and. (pl%levelg(plind(1:npltpenc)) >= irec) &