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   "source": [
    "Example Using the Earthquake network\n",
    "================================"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "In this example I will try to create the Alarm Bayesian Network using pgmpy and do some simple queries on the network.\n",
    "This network is mentioned in Bayesian Artificial Intelligence - Section 2.5.1 (https://bayesian-intelligence.com/publications/bai/book/BAI_Chapter2.pdf)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Importing Library\n",
    "from pgmpy.models import BayesianNetwork\n",
    "from pgmpy.inference import VariableElimination"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Defining network structure\n",
    "\n",
    "alarm_model = BayesianNetwork(\n",
    "    [\n",
    "        (\"Burglary\", \"Alarm\"),\n",
    "        (\"Earthquake\", \"Alarm\"),\n",
    "        (\"Alarm\", \"JohnCalls\"),\n",
    "        (\"Alarm\", \"MaryCalls\"),\n",
    "    ]\n",
    ")\n",
    "\n",
    "# Defining the parameters using CPT\n",
    "from pgmpy.factors.discrete import TabularCPD\n",
    "\n",
    "cpd_burglary = TabularCPD(\n",
    "    variable=\"Burglary\", variable_card=2, values=[[0.999], [0.001]]\n",
    ")\n",
    "cpd_earthquake = TabularCPD(\n",
    "    variable=\"Earthquake\", variable_card=2, values=[[0.998], [0.002]]\n",
    ")\n",
    "cpd_alarm = TabularCPD(\n",
    "    variable=\"Alarm\",\n",
    "    variable_card=2,\n",
    "    values=[[0.999, 0.71, 0.06, 0.05], [0.001, 0.29, 0.94, 0.95]],\n",
    "    evidence=[\"Burglary\", \"Earthquake\"],\n",
    "    evidence_card=[2, 2],\n",
    ")\n",
    "cpd_johncalls = TabularCPD(\n",
    "    variable=\"JohnCalls\",\n",
    "    variable_card=2,\n",
    "    values=[[0.95, 0.1], [0.05, 0.9]],\n",
    "    evidence=[\"Alarm\"],\n",
    "    evidence_card=[2],\n",
    ")\n",
    "cpd_marycalls = TabularCPD(\n",
    "    variable=\"MaryCalls\",\n",
    "    variable_card=2,\n",
    "    values=[[0.1, 0.7], [0.9, 0.3]],\n",
    "    evidence=[\"Alarm\"],\n",
    "    evidence_card=[2],\n",
    ")\n",
    "\n",
    "# Associating the parameters with the model structure\n",
    "alarm_model.add_cpds(\n",
    "    cpd_burglary, cpd_earthquake, cpd_alarm, cpd_johncalls, cpd_marycalls\n",
    ")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "True"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Checking if the cpds are valid for the model\n",
    "alarm_model.check_model()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "NodeView(('Burglary', 'Alarm', 'Earthquake', 'JohnCalls', 'MaryCalls'))"
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Viewing nodes of the model\n",
    "alarm_model.nodes()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "OutEdgeView([('Burglary', 'Alarm'), ('Alarm', 'JohnCalls'), ('Alarm', 'MaryCalls'), ('Earthquake', 'Alarm')])"
      ]
     },
     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Viewing edges of the model\n",
    "alarm_model.edges()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(Burglary ⟂ Earthquake)"
      ]
     },
     "execution_count": 7,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Checking independcies of a node\n",
    "alarm_model.local_independencies(\"Burglary\")"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(JohnCalls ⟂ Burglary, MaryCalls, Earthquake | Alarm)\n",
       "(JohnCalls ⟂ MaryCalls, Earthquake | Burglary, Alarm)\n",
       "(JohnCalls ⟂ Burglary, Earthquake | Alarm, MaryCalls)\n",
       "(JohnCalls ⟂ Burglary, MaryCalls | Alarm, Earthquake)\n",
       "(JohnCalls ⟂ Earthquake | Burglary, MaryCalls, Alarm)\n",
       "(JohnCalls ⟂ MaryCalls | Burglary, Earthquake, Alarm)\n",
       "(JohnCalls ⟂ Burglary | Alarm, MaryCalls, Earthquake)\n",
       "(MaryCalls ⟂ JohnCalls, Burglary, Earthquake | Alarm)\n",
       "(MaryCalls ⟂ Burglary, Earthquake | JohnCalls, Alarm)\n",
       "(MaryCalls ⟂ JohnCalls, Earthquake | Burglary, Alarm)\n",
       "(MaryCalls ⟂ JohnCalls, Burglary | Alarm, Earthquake)\n",
       "(MaryCalls ⟂ Earthquake | JohnCalls, Burglary, Alarm)\n",
       "(MaryCalls ⟂ Burglary | JohnCalls, Alarm, Earthquake)\n",
       "(MaryCalls ⟂ JohnCalls | Burglary, Earthquake, Alarm)\n",
       "(Earthquake ⟂ Burglary)\n",
       "(Earthquake ⟂ JohnCalls, MaryCalls | Alarm)\n",
       "(Earthquake ⟂ MaryCalls | JohnCalls, Alarm)\n",
       "(Earthquake ⟂ JohnCalls, MaryCalls | Burglary, Alarm)\n",
       "(Earthquake ⟂ JohnCalls | Alarm, MaryCalls)\n",
       "(Earthquake ⟂ MaryCalls | JohnCalls, Burglary, Alarm)\n",
       "(Earthquake ⟂ JohnCalls | Burglary, MaryCalls, Alarm)\n",
       "(Burglary ⟂ Earthquake)\n",
       "(Burglary ⟂ JohnCalls, MaryCalls | Alarm)\n",
       "(Burglary ⟂ MaryCalls | JohnCalls, Alarm)\n",
       "(Burglary ⟂ JohnCalls | Alarm, MaryCalls)\n",
       "(Burglary ⟂ JohnCalls, MaryCalls | Alarm, Earthquake)\n",
       "(Burglary ⟂ MaryCalls | JohnCalls, Alarm, Earthquake)\n",
       "(Burglary ⟂ JohnCalls | Alarm, MaryCalls, Earthquake)"
      ]
     },
     "execution_count": 8,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Listing all Independencies\n",
    "alarm_model.get_independencies()"
   ]
  }
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