numpy_structarray_access.ipynb

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      "1.10.1\n"
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    "import numpy as np\n",
    "print(np.__version__)"
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   "source": [
    "Access so an element of an array is quie fast"
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      "CPU times: user 0 ns, sys: 0 ns, total: 0 ns\n",
      "Wall time: 198 µs\n",
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      "Wall time: 20.7 µs\n"
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   "source": [
    "%time arr = np.zeros((1000,1000))\n",
    "%time arr[500,500]"
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   "source": [
    "Trying to access a single element of an array that is within a dtype definition takes almost 4 seconds (5 order of magnitude more?!)"
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      "CPU times: user 0 ns, sys: 0 ns, total: 0 ns\n",
      "Wall time: 74.1 µs\n",
      "CPU times: user 3.65 s, sys: 293 ms, total: 3.95 s\n",
      "Wall time: 3.94 s\n"
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   "source": [
    "mydtype = np.dtype([('metainformation', np.float64), ('data', np.float64, (1000,1000))])\n",
    "%time strarr = np.zeros(25, dtype=mydtype)\n",
    "%time strarr[2]['data'][500,500]"
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