The unique handling of division by zero across Pandas and NumPy

divbyzero.ipynb

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      "pd: 0.13.1\n",
      "np: 1.8.0\n"
     ]
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   "source": [
    "import pandas as pd\n",
    "import numpy as np\n",
    "print \"pd:\", pd.__version__\n",
    "print \"np:\", np.__version__"
   ]
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      "text/html": [
       "<div style=\"max-height:1000px;max-width:1500px;overflow:auto;\">\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>0 / 0</th>\n",
       "      <th>0 / 0.0</th>\n",
       "      <th>0.0 / 0</th>\n",
       "      <th>0.0 / 0.0</th>\n",
       "      <th>1 / 0</th>\n",
       "      <th>1 / 0.0</th>\n",
       "      <th>1.0 / 0</th>\n",
       "      <th>1.0 / 0.0</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>pd</th>\n",
       "      <td> inf</td>\n",
       "      <td> nan</td>\n",
       "      <td> inf</td>\n",
       "      <td> nan</td>\n",
       "      <td> inf</td>\n",
       "      <td> inf</td>\n",
       "      <td> inf</td>\n",
       "      <td> inf</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>np</th>\n",
       "      <td>   0</td>\n",
       "      <td> nan</td>\n",
       "      <td> nan</td>\n",
       "      <td> nan</td>\n",
       "      <td>   0</td>\n",
       "      <td> inf</td>\n",
       "      <td> inf</td>\n",
       "      <td> inf</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>2 rows × 8 columns</p>\n",
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      "text/plain": [
       "   0 / 0 0 / 0.0 0.0 / 0 0.0 / 0.0 1 / 0 1 / 0.0 1.0 / 0 1.0 / 0.0\n",
       "pd   inf     nan     inf       nan   inf     inf     inf       inf\n",
       "np     0     nan     nan       nan     0     inf     inf       inf\n",
       "\n",
       "[2 rows x 8 columns]"
      ]
     },
     "execution_count": 10,
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   ],
   "source": [
    "index = []\n",
    "data = []\n",
    "for arr_name, arr in [(\"pd\", pd.Series), (\"np\", np.array)]:\n",
    "    cols = []\n",
    "    d = []\n",
    "    for divisor in [0, 0.0, 1, 1.0]:\n",
    "        for dividend in [0, 0.0]:\n",
    "            cols.append(\"%s / %s\" %(divisor, dividend))\n",
    "            d.append(repr((arr([divisor]) / dividend)[0]))\n",
    "    data.append(d)\n",
    "    index.append(arr_name)\n",
    "df = pd.DataFrame(data)\n",
    "df.index = index\n",
    "df.columns = cols\n",
    "df"
   ]
  }
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