Merge pull request #40 from BenLauwens/release-0.4

Update example Ross 7.7

Author: BenLauwens

examples/Ross_Simulation_7.7_A_repair_problem.ipynb

@@ -12,13 +12,8 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "## Description"
-   ]
-  },
-  {
-   "cell_type": "markdown",
-   "metadata": {},
-   "source": [
+    "## Description\n",
+    "\n",
     "A system needs $n$ working machines to be operational. To guard against machine breakdown, additional machines are kept available as spares. Whenever a machine breaks down it is immediately replaced by a spare and is itself sent to the repair facility, which consists of a single repairperson who repairs failed machines one at a time. Once a failed machine has been repaired it becomes available as a spare to be used when the need arises. All repair times are independent random variables having the common distribution function $G$. Each time a machine is put into use the amount of time it functions before breaking down is a random variable, independent of the past, having distribution function $F$.\n",
     "\n",
     "The system is said to “crash” when a machine fails and no spares are available. Assuming that there are initially $n + s$ functional machines of which $n$ are put in use and $s$ are kept as spares, we are interested in simulating this system so as to approximate $E[T]$, where $T$ is the time at which the system crashes."
@@ -53,7 +48,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 13,
    "metadata": {
     "collapsed": true
    },
@@ -73,7 +68,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 14,
    "metadata": {
     "collapsed": false
    },
@@ -84,7 +79,11 @@
     "const S = 3\n",
     "const SEED = 150\n",
     "const LAMBDA = 100\n",
-    "const MU = 1;"
+    "const MU = 1\n",
+    "\n",
+    "srand(SEED)\n",
+    "F = Exponential(LAMBDA)\n",
+    "G = Exponential(MU);"
    ]
   },
   {
@@ -96,38 +95,47 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 15,
    "metadata": {
     "collapsed": false
    },
-   "outputs": [],
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "machine (generic function with 1 method)"
+      ]
+     },
+     "execution_count": 15,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
    "source": [
     "@resumable function machine(sim::Simulation, repair_facility::Resource, spares::Store{Coroutine})\n",
-    "    dist_work = Exponential(LAMBDA)\n",
-    "    dist_repair = Exponential(MU)\n",
     "    while true\n",
     "        try\n",
     "            @yield Timeout(sim, Inf)\n",
-    "        catch(exc)\n",
-    "    end\n",
-    "    #println(\"At time $(now(sim)): $(active_process(sim)) starts working.\")\n",
-    "    @yield Timeout(sim, rand(dist_work))\n",
-    "    #println(\"At time $(now(sim)): $(active_process(sim)) stops working.\")\n",
-    "    get_spare = Get(spares)\n",
-    "    @yield get_spare | Timeout(sim, 0.0)\n",
-    "    if state(get_spare) != SimJulia.idle\n",
-    "        interrupt(value(get_spare))\n",
-    "    else\n",
-    "        throw(SimJulia.StopSimulation(\"No more spares!\"))\n",
+    "        catch exc\n",
+    "        end\n",
+    "        #println(\"At time $(now(sim)): $(active_process(sim)) starts working.\")\n",
+    "        @yield Timeout(sim, rand(F))\n",
+    "        #println(\"At time $(now(sim)): $(active_process(sim)) stops working.\")\n",
+    "        get_spare = Get(spares)\n",
+    "        @yield get_spare | Timeout(sim, 0.0)\n",
+    "        if state(get_spare) != SimJulia.idle\n",
+    "            interrupt(value(get_spare))\n",
+    "        else\n",
+    "            throw(SimJulia.StopSimulation(\"No more spares!\"))\n",
+    "        end\n",
+    "        @yield Request(repair_facility)\n",
+    "        #println(\"At time $(now(sim)): $(active_process(sim)) repair starts.\")\n",
+    "        @yield Timeout(sim, rand(G))\n",
+    "        @yield Release(repair_facility)\n",
+    "        #println(\"At time $(now(sim)): $(active_process(sim)) is repaired.\")\n",
+    "        @yield Put(spares, active_process(sim))\n",
     "    end\n",
-    "    @yield Request(repair_facility)\n",
-    "    #println(\"At time $(now(sim)): $(active_process(sim)) repair starts.\")\n",
-    "    @yield Timeout(sim, rand(dist_repair))\n",
-    "    @yield Release(repair_facility)\n",
-    "    #println(\"At time $(now(sim)): $(active_process(sim)) is repaired.\")\n",
-    "    @yield Put(spares, active_process(sim))\n",
-    "    end\n",
-    "end\n"
+    "end"
    ]
   },
   {
@@ -139,11 +147,22 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 16,
    "metadata": {
     "collapsed": false
    },
-   "outputs": [],
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "start_sim (generic function with 1 method)"
+      ]
+     },
+     "execution_count": 16,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
    "source": [
     "@resumable function start_sim(sim::Simulation, repair_facility::Resource, spares::Store{Coroutine})\n",
     "    procs = Coroutine[]\n",
@@ -169,11 +188,22 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 17,
    "metadata": {
     "collapsed": false
    },
-   "outputs": [],
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "sim_repair (generic function with 1 method)"
+      ]
+     },
+     "execution_count": 17,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
    "source": [
     "function sim_repair()\n",
     "    sim = Simulation()\n",
@@ -196,20 +226,41 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 18,
    "metadata": {
     "collapsed": false
    },
-   "outputs": [],
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "At time 5573.772841846017: No more spares!\n",
+      "At time 1438.0294516073466: No more spares!\n",
+      "At time 7077.413276961621: No more spares!\n",
+      "At time 7286.490682742159: No more spares!\n",
+      "At time 6820.788098062124: No more spares!\n",
+      "5639.298870243853\n"
+     ]
+    }
+   ],
    "source": [
-    "srand(SEED)\n",
     "results = Float64[]\n",
     "for i=1:RUNS\n",
     "    push!(results, sim_repair())\n",
     "end\n",
     "println(sum(results)/RUNS)"
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": true
+   },
+   "outputs": [],
+   "source": []
+  },
   {
    "cell_type": "code",
    "execution_count": null,