Chapter 1/Ch1_Introduction.ipynb

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   "source": [
    "# Deep Reinforcement Learning <em> in Action </em>\n",
    "## Ch 1. Introduction\n",
    "### Dynamic Programming"
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    "def fib(n):\n",
    "    if n <= 1:\n",
    "        return n\n",
    "    else:\n",
    "        return fib(n - 1) + fib(n - 2)"
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    "fib(7)"
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    "mem = {0:0, 1:1}\n",
    "\n",
    "def fib_mem(n):\n",
    "    if n not in mem:\n",
    "        mem[n] = fib(n - 1) + fib(n - 2)\n",
    "    return mem[n]"
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    "fib_mem(7)"
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   "source": [
    "### Time Performance"
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      "4.4 s ± 844 ms per loop (mean ± std. dev. of 7 runs, 1 loop each)\n"
     ]
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   "source": [
    "%timeit fib(35)\n",
    "# We get 5.54 seconds to run with n=35"
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      "319 ns ± 274 ns per loop (mean ± std. dev. of 7 runs, 1 loop each)\n"
     ]
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   "source": [
    "%timeit fib_mem(35)\n",
    "# We get 412 ns to run with n=35"
   ]
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   "execution_count": null,
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