except vs get

exceptget.ipynb

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    "# `except KeyError` performance\n",
    "\n",
    "If it's common that the key isn't in the dictionary, then it makes a lot of sense to access it via `.get` with a default. If it's truly exceptional it doesn't exist and you'll want to do something special, then a `try` block is faster in the common case."
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    "d = {'foo': 3}"
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     "text": [
      "62.3 ns ± 3.83 ns per loop (mean ± std. dev. of 7 runs, 10000000 loops each)\n"
     ]
    }
   ],
   "source": [
    "%%timeit\n",
    "try:\n",
    "    result = d['foo'] * 2\n",
    "except KeyError:\n",
    "    result = 0"
   ]
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     "text": [
      "89.8 ns ± 1.56 ns per loop (mean ± std. dev. of 7 runs, 10000000 loops each)\n"
     ]
    }
   ],
   "source": [
    "%%timeit\n",
    "result = d.get('foo', 0) * 2"
   ]
  },
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   "cell_type": "code",
   "execution_count": 151,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "267 ns ± 25 ns per loop (mean ± std. dev. of 7 runs, 1000000 loops each)\n"
     ]
    }
   ],
   "source": [
    "%%timeit\n",
    "try:\n",
    "    result = d['bar'] * 2\n",
    "except KeyError:\n",
    "    result = 0"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 152,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "93.2 ns ± 5.52 ns per loop (mean ± std. dev. of 7 runs, 10000000 loops each)\n"
     ]
    }
   ],
   "source": [
    "%%timeit\n",
    "result = d.get('bar', 0) * 2"
   ]
  },
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   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
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