notebooks/find_null_values_in_any_column.ipynb

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   "source": [
    "# Find rows with null values in any column\n",
    "\n",
    "Use `DataFrame.isnull().any(axis=1)`\n",
    "\n",
    "via [Python Pandas How to select rows with one or more nulls from a DataFrame without listing columns explicitly? - Stack Overflow](https://stackoverflow.com/questions/14247586/python-pandas-how-to-select-rows-with-one-or-more-nulls-from-a-dataframe-without)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import pandas as pd"
   ]
  },
  {
   "cell_type": "code",
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   "outputs": [
    {
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       "      <th></th>\n",
       "      <th>col1</th>\n",
       "      <th>col2</th>\n",
       "    </tr>\n",
       "  </thead>\n",
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       "      <th>0</th>\n",
       "      <td>Test Value 1</td>\n",
       "      <td>None</td>\n",
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       "      <th>1</th>\n",
       "      <td>Test Value 2</td>\n",
       "      <td>Test Value 3</td>\n",
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       "      <td>Test Value 4</td>\n",
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      "text/plain": [
       "           col1          col2\n",
       "0  Test Value 1          None\n",
       "1  Test Value 2  Test Value 3\n",
       "2          None  Test Value 4"
      ]
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     "execution_count": 2,
     "metadata": {},
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   ],
   "source": [
    "# Make some toy data\n",
    "\n",
    "data = [\n",
    "    ('Test Value 1', None),\n",
    "    ('Test Value 2', 'Test Value 3'),\n",
    "    (None, 'Test Value 4'),\n",
    "    \n",
    "]\n",
    "columns = ['col1', 'col2']\n",
    "\n",
    "df = pd.DataFrame.from_records(data, columns=columns)\n",
    "\n",
    "df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0     True\n",
       "1    False\n",
       "2     True\n",
       "dtype: bool"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Show rows that have nulls in any column\n",
    "df.isnull().any(axis=1)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
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       "      <td>None</td>\n",
       "      <td>Test Value 4</td>\n",
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       "           col1          col2\n",
       "0  Test Value 1          None\n",
       "2          None  Test Value 4"
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     "execution_count": 4,
     "metadata": {},
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   ],
   "source": [
    "# You can also use this to index the original DataFrame\n",
    "df[df.isnull().any(axis=1)]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
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