2_c_apply_a_function_to_a_column.ipynb

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    "apply a function to a dataframe column"
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  {
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   "source": [
    "import pandas as pd\n",
    "df = pd.DataFrame([['AA', 1], ['BB', 2], ['CC', 3]], columns=['name', 'value'])"
   ]
  },
  {
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   "execution_count": 2,
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       "<div>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>value</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>AA</td>\n",
       "      <td>1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>BB</td>\n",
       "      <td>2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>CC</td>\n",
       "      <td>3</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
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      "text/plain": [
       "  name  value\n",
       "0   AA      1\n",
       "1   BB      2\n",
       "2   CC      3"
      ]
     },
     "execution_count": 2,
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    "df"
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   "cell_type": "code",
   "execution_count": 3,
   "metadata": {
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   "source": [
    "def function_1(val_1):\n",
    "    return \"prefix_\" + str(val_1)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {
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   "source": [
    "df['name'] = df['name'].map(function_1)"
   ]
  },
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   "cell_type": "code",
   "execution_count": 5,
   "metadata": {
    "collapsed": false
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    {
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       "<div>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>value</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>prefix_AA</td>\n",
       "      <td>1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>prefix_BB</td>\n",
       "      <td>2</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>prefix_CC</td>\n",
       "      <td>3</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
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      "text/plain": [
       "        name  value\n",
       "0  prefix_AA      1\n",
       "1  prefix_BB      2\n",
       "2  prefix_CC      3"
      ]
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     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
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   "source": [
    "df"
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   "execution_count": null,
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    "collapsed": true
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   "outputs": [],
   "source": []
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