Performance - generate n random digits.ipynb

Performance - generate n random digits.ipynb

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    {
      "metadata": {
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      "source": "# define functions that generate random string using the alphabet\nimport random\nimport string\nfrom itertools import cycle, islice\n\ndef generate_random_string(n, alphabet=string.digits, choice=random.choice):\n    return ''.join([choice(alphabet) for _ in range(n)])\n\n\ndef make_random_generator(alphabet=string.digits, getrandbits=random.getrandbits):\n    letters = alphabet.encode('ascii')\n    nbytes = 256    \n    naligned = nbytes - nbytes % len(letters)\n    table = bytes.maketrans(bytes(range(naligned)),\n                            bytes(islice(cycle(letters), naligned)))\n    bytes2delete = bytes(range(naligned, nbytes))\n    def generate(n):\n        L = []\n        while n > 0:\n            chunk = getrandbits(8*n).to_bytes(n, 'big').translate(table, bytes2delete)\n            n -= len(chunk)\n            L.append(chunk)\n        return b''.join(L).decode('ascii')\n    return generate\n\ngenerate_random_string_tr = make_random_generator()\ngenerate_random_string_tr.__name__ = 'generate_random_string_tr'",
      "execution_count": 1,
      "outputs": []
    },
    {
      "metadata": {
        "trusted": true
      },
      "cell_type": "code",
      "source": "%timeit generate_random_string(32)",
      "execution_count": 2,
      "outputs": [
        {
          "name": "stdout",
          "output_type": "stream",
          "text": "46.4 µs ± 1.7 µs per loop (mean ± std. dev. of 7 runs, 10000 loops each)\n"
        }
      ]
    },
    {
      "metadata": {
        "trusted": true
      },
      "cell_type": "code",
      "source": "%timeit generate_random_string_tr(32)",
      "execution_count": 3,
      "outputs": [
        {
          "name": "stdout",
          "output_type": "stream",
          "text": "3.44 µs ± 34.5 ns per loop (mean ± std. dev. of 7 runs, 100000 loops each)\n"
        }
      ]
    },
    {
      "metadata": {
        "trusted": true
      },
      "cell_type": "code",
      "source": "import reporttime  # https://gist.github.com/zed/4276624#file-reporttime-py\n\nfuncs = [generate_random_string, generate_random_string_tr]\nfor n in [5, 10, 20]:\n    reporttime.measure(funcs, args=[1<<n])",
      "execution_count": 4,
      "outputs": [
        {
          "name": "stdout",
          "output_type": "stream",
          "text": "name                           time ratio comment\ngenerate_random_string_tr  3.7 usec  1.00 [32]\ngenerate_random_string    45.9 usec 12.40 [32]\nname                           time  ratio comment\ngenerate_random_string_tr 13.8 usec   1.00 [1024]\ngenerate_random_string    1.43 msec 103.57 [1024]\nname                           time  ratio comment\ngenerate_random_string_tr 8.21 msec   1.00 [1048576]\ngenerate_random_string    1.44  sec 174.99 [1048576]\n"
        }
      ]
    }
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        "description": "Performance - generate n random digits.ipynb",
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