{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "[Back to the GitHub repository](https://github.com/rasbt/python_reference)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Sebastian Raschka 28/01/2015 \n",
      "\n",
      "CPython 3.4.2\n",
      "IPython 2.3.1\n",
      "\n",
      "pandas 0.15.2\n"
     ]
    }
   ],
   "source": [
    "%load_ext watermark\n",
    "%watermark -a 'Sebastian Raschka' -v -d -p pandas"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<font size=\"1.5em\">[More information](http://nbviewer.ipython.org/github/rasbt/python_reference/blob/master/ipython_magic/watermark.ipynb) about the `watermark` magic command extension.</font>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Things in Pandas I Wish I'd Known Earlier"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "This is just a small but growing collection of pandas snippets that I find occasionally and particularly useful -- consider it as my personal notebook. Suggestions, tips, and contributions are very, very welcome!"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Sections"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "- [Loading Some Example Data](#Loading-Some-Example-Data)\n",
    "- [Renaming Columns](#Renaming-Columns)\n",
    "    - [Converting Column Names to Lowercase](#Converting-Column-Names-to-Lowercase)\n",
    "    - [Renaming Particular Columns](#Renaming-Particular-Columns)\n",
    "- [Applying Computations Rows-wise](#Applying-Computations-Rows-wise)\n",
    "    - [Changing Values in a Column](#Changing-Values-in-a-Column)\n",
    "    - [Adding a New Column](#Adding-a-New-Column)\n",
    "    - [Applying Functions to Multiple Columns](#Applying-Functions-to-Multiple-Columns)\n",
    "- [Missing Values aka NaNs](#Missing-Values-aka-NaNs)\n",
    "    - [Counting Rows with NaNs](#Counting-Rows-with-NaNs)\n",
    "    - [Selecting NaN Rows](#Selecting-NaN-Rows)\n",
    "    - [Selecting non-NaN Rows](#Selecting-non-NaN-Rows)\n",
    "    - [Filling NaN Rows](#Filling-NaN-Rows)\n",
    "- [Appending Rows to a DataFrame](#Appending-Rows-to-a-DataFrame)\n",
    "- [Sorting and Reindexing DataFrames](#Sorting-and-Reindexing-DataFrames)\n",
    "- [Updating Columns](#Updating-Columns)\n",
    "- [Chaining Conditions - Using Bitwise Operators](#Chaining-Conditions---Using-Bitwise-Operators)\n",
    "- [Column Types](#Column-Types)\n",
    "    - [Printing Column Types](#Printing-Column-Types)\n",
    "    - [Selecting by Column Type](#Selecting-by-Column-Type)\n",
    "    - [Converting Column Types](#Converting-Column-Types)\n",
    "- [If-tests](#If-tests)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Loading Some Example Data"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "[[back to section overview](#Sections)]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "I am heavily into sports prediction (via a machine learning approach) these days. So, let us use a (very) small subset of the soccer data that I am just working with."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>PLAYER</th>\n",
       "      <th>SALARY</th>\n",
       "      <th>GP</th>\n",
       "      <th>G</th>\n",
       "      <th>A</th>\n",
       "      <th>SOT</th>\n",
       "      <th>PPG</th>\n",
       "      <th>P</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>     Sergio Agüero\\n Forward — Manchester City</td>\n",
       "      <td> $19.2m</td>\n",
       "      <td> 16</td>\n",
       "      <td> 14</td>\n",
       "      <td>  3</td>\n",
       "      <td> 34</td>\n",
       "      <td> 13.12</td>\n",
       "      <td> 209.98</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>              Eden Hazard\\n Midfield — Chelsea</td>\n",
       "      <td> $18.9m</td>\n",
       "      <td> 21</td>\n",
       "      <td>  8</td>\n",
       "      <td>  4</td>\n",
       "      <td> 17</td>\n",
       "      <td> 13.05</td>\n",
       "      <td> 274.04</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>            Alexis Sánchez\\n Forward — Arsenal</td>\n",
       "      <td> $17.6m</td>\n",
       "      <td>NaN</td>\n",
       "      <td> 12</td>\n",
       "      <td>  7</td>\n",
       "      <td> 29</td>\n",
       "      <td> 11.19</td>\n",
       "      <td> 223.86</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>       Yaya Touré\\n Midfield — Manchester City</td>\n",
       "      <td> $16.6m</td>\n",
       "      <td> 18</td>\n",
       "      <td>  7</td>\n",
       "      <td>  1</td>\n",
       "      <td> 19</td>\n",
       "      <td> 10.99</td>\n",
       "      <td> 197.91</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td> Ángel Di María\\n Midfield — Manchester United</td>\n",
       "      <td> $15.0m</td>\n",
       "      <td> 13</td>\n",
       "      <td>  3</td>\n",
       "      <td>NaN</td>\n",
       "      <td> 13</td>\n",
       "      <td> 10.17</td>\n",
       "      <td> 132.23</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>         Santiago Cazorla\\n Midfield — Arsenal</td>\n",
       "      <td> $14.8m</td>\n",
       "      <td> 20</td>\n",
       "      <td>  4</td>\n",
       "      <td>NaN</td>\n",
       "      <td> 20</td>\n",
       "      <td>  9.97</td>\n",
       "      <td>    NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>      David Silva\\n Midfield — Manchester City</td>\n",
       "      <td> $14.3m</td>\n",
       "      <td> 15</td>\n",
       "      <td>  6</td>\n",
       "      <td>  2</td>\n",
       "      <td> 11</td>\n",
       "      <td> 10.35</td>\n",
       "      <td> 155.26</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>            Cesc Fàbregas\\n Midfield — Chelsea</td>\n",
       "      <td> $14.0m</td>\n",
       "      <td> 20</td>\n",
       "      <td>  2</td>\n",
       "      <td> 14</td>\n",
       "      <td> 10</td>\n",
       "      <td> 10.47</td>\n",
       "      <td> 209.49</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>          Saido Berahino\\n Forward — West Brom</td>\n",
       "      <td> $13.8m</td>\n",
       "      <td> 21</td>\n",
       "      <td>  9</td>\n",
       "      <td>  0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>         Steven Gerrard\\n Midfield — Liverpool</td>\n",
       "      <td> $13.8m</td>\n",
       "      <td> 20</td>\n",
       "      <td>  5</td>\n",
       "      <td>  1</td>\n",
       "      <td> 11</td>\n",
       "      <td>  7.50</td>\n",
       "      <td> 150.01</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "                                          PLAYER  SALARY  GP   G   A  SOT  \\\n",
       "0      Sergio Agüero\\n Forward — Manchester City  $19.2m  16  14   3   34   \n",
       "1               Eden Hazard\\n Midfield — Chelsea  $18.9m  21   8   4   17   \n",
       "2             Alexis Sánchez\\n Forward — Arsenal  $17.6m NaN  12   7   29   \n",
       "3        Yaya Touré\\n Midfield — Manchester City  $16.6m  18   7   1   19   \n",
       "4  Ángel Di María\\n Midfield — Manchester United  $15.0m  13   3 NaN   13   \n",
       "5          Santiago Cazorla\\n Midfield — Arsenal  $14.8m  20   4 NaN   20   \n",
       "6       David Silva\\n Midfield — Manchester City  $14.3m  15   6   2   11   \n",
       "7             Cesc Fàbregas\\n Midfield — Chelsea  $14.0m  20   2  14   10   \n",
       "8           Saido Berahino\\n Forward — West Brom  $13.8m  21   9   0   20   \n",
       "9          Steven Gerrard\\n Midfield — Liverpool  $13.8m  20   5   1   11   \n",
       "\n",
       "     PPG       P  \n",
       "0  13.12  209.98  \n",
       "1  13.05  274.04  \n",
       "2  11.19  223.86  \n",
       "3  10.99  197.91  \n",
       "4  10.17  132.23  \n",
       "5   9.97     NaN  \n",
       "6  10.35  155.26  \n",
       "7  10.47  209.49  \n",
       "8   7.02  147.43  \n",
       "9   7.50  150.01  "
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import pandas as pd\n",
    "\n",
    "df = pd.read_csv('https://raw.githubusercontent.com/rasbt/python_reference/master/Data/some_soccer_data.csv')\n",
    "df"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Renaming Columns"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "[[back to section overview](#Sections)]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Converting Column Names to Lowercase"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>gp</th>\n",
       "      <th>g</th>\n",
       "      <th>a</th>\n",
       "      <th>sot</th>\n",
       "      <th>ppg</th>\n",
       "      <th>p</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>    Cesc Fàbregas\\n Midfield — Chelsea</td>\n",
       "      <td> $14.0m</td>\n",
       "      <td> 20</td>\n",
       "      <td> 2</td>\n",
       "      <td> 14</td>\n",
       "      <td> 10</td>\n",
       "      <td> 10.47</td>\n",
       "      <td> 209.49</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>  Saido Berahino\\n Forward — West Brom</td>\n",
       "      <td> $13.8m</td>\n",
       "      <td> 21</td>\n",
       "      <td> 9</td>\n",
       "      <td>  0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td> Steven Gerrard\\n Midfield — Liverpool</td>\n",
       "      <td> $13.8m</td>\n",
       "      <td> 20</td>\n",
       "      <td> 5</td>\n",
       "      <td>  1</td>\n",
       "      <td> 11</td>\n",
       "      <td>  7.50</td>\n",
       "      <td> 150.01</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "                                  player  salary  gp  g   a  sot    ppg  \\\n",
       "7     Cesc Fàbregas\\n Midfield — Chelsea  $14.0m  20  2  14   10  10.47   \n",
       "8   Saido Berahino\\n Forward — West Brom  $13.8m  21  9   0   20   7.02   \n",
       "9  Steven Gerrard\\n Midfield — Liverpool  $13.8m  20  5   1   11   7.50   \n",
       "\n",
       "        p  \n",
       "7  209.49  \n",
       "8  147.43  \n",
       "9  150.01  "
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Converting column names to lowercase\n",
    "\n",
    "df.columns = [c.lower() for c in df.columns]\n",
    "\n",
    "# or\n",
    "# df.rename(columns=lambda x : x.lower())\n",
    "\n",
    "df.tail(3)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Renaming Particular Columns"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>    Cesc Fàbregas\\n Midfield — Chelsea</td>\n",
       "      <td> $14.0m</td>\n",
       "      <td> 20</td>\n",
       "      <td> 2</td>\n",
       "      <td> 14</td>\n",
       "      <td> 10</td>\n",
       "      <td> 10.47</td>\n",
       "      <td> 209.49</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>  Saido Berahino\\n Forward — West Brom</td>\n",
       "      <td> $13.8m</td>\n",
       "      <td> 21</td>\n",
       "      <td> 9</td>\n",
       "      <td>  0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td> Steven Gerrard\\n Midfield — Liverpool</td>\n",
       "      <td> $13.8m</td>\n",
       "      <td> 20</td>\n",
       "      <td> 5</td>\n",
       "      <td>  1</td>\n",
       "      <td> 11</td>\n",
       "      <td>  7.50</td>\n",
       "      <td> 150.01</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "                                  player  salary  games  goals  assists  \\\n",
       "7     Cesc Fàbregas\\n Midfield — Chelsea  $14.0m     20      2       14   \n",
       "8   Saido Berahino\\n Forward — West Brom  $13.8m     21      9        0   \n",
       "9  Steven Gerrard\\n Midfield — Liverpool  $13.8m     20      5        1   \n",
       "\n",
       "   shots_on_target  points_per_game  points  \n",
       "7               10            10.47  209.49  \n",
       "8               20             7.02  147.43  \n",
       "9               11             7.50  150.01  "
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df = df.rename(columns={'p': 'points', \n",
    "                        'gp': 'games',\n",
    "                        'sot': 'shots_on_target',\n",
    "                        'g': 'goals',\n",
    "                        'ppg': 'points_per_game',\n",
    "                        'a': 'assists',})\n",
    "\n",
    "df.tail(3)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Applying Computations Rows-wise"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "[[back to section overview](#Sections)]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Changing Values in a Column"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>    Santiago Cazorla\\n Midfield — Arsenal</td>\n",
       "      <td> 14.8</td>\n",
       "      <td> 20</td>\n",
       "      <td> 4</td>\n",
       "      <td>NaN</td>\n",
       "      <td> 20</td>\n",
       "      <td>  9.97</td>\n",
       "      <td>    NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td> David Silva\\n Midfield — Manchester City</td>\n",
       "      <td> 14.3</td>\n",
       "      <td> 15</td>\n",
       "      <td> 6</td>\n",
       "      <td>  2</td>\n",
       "      <td> 11</td>\n",
       "      <td> 10.35</td>\n",
       "      <td> 155.26</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>       Cesc Fàbregas\\n Midfield — Chelsea</td>\n",
       "      <td> 14.0</td>\n",
       "      <td> 20</td>\n",
       "      <td> 2</td>\n",
       "      <td> 14</td>\n",
       "      <td> 10</td>\n",
       "      <td> 10.47</td>\n",
       "      <td> 209.49</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>     Saido Berahino\\n Forward — West Brom</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td> 9</td>\n",
       "      <td>  0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>    Steven Gerrard\\n Midfield — Liverpool</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 20</td>\n",
       "      <td> 5</td>\n",
       "      <td>  1</td>\n",
       "      <td> 11</td>\n",
       "      <td>  7.50</td>\n",
       "      <td> 150.01</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "                                     player salary  games  goals  assists  \\\n",
       "5     Santiago Cazorla\\n Midfield — Arsenal   14.8     20      4      NaN   \n",
       "6  David Silva\\n Midfield — Manchester City   14.3     15      6        2   \n",
       "7        Cesc Fàbregas\\n Midfield — Chelsea   14.0     20      2       14   \n",
       "8      Saido Berahino\\n Forward — West Brom   13.8     21      9        0   \n",
       "9     Steven Gerrard\\n Midfield — Liverpool   13.8     20      5        1   \n",
       "\n",
       "   shots_on_target  points_per_game  points  \n",
       "5               20             9.97     NaN  \n",
       "6               11            10.35  155.26  \n",
       "7               10            10.47  209.49  \n",
       "8               20             7.02  147.43  \n",
       "9               11             7.50  150.01  "
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Processing `salary` column\n",
    "\n",
    "df['salary'] = df['salary'].apply(lambda x: x.strip('$m'))\n",
    "df.tail()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Adding a New Column"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>    Cesc Fàbregas\\n Midfield — Chelsea</td>\n",
       "      <td> 14.0</td>\n",
       "      <td> 20</td>\n",
       "      <td> 2</td>\n",
       "      <td> 14</td>\n",
       "      <td> 10</td>\n",
       "      <td> 10.47</td>\n",
       "      <td> 209.49</td>\n",
       "      <td> </td>\n",
       "      <td> </td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>  Saido Berahino\\n Forward — West Brom</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td> 9</td>\n",
       "      <td>  0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "      <td> </td>\n",
       "      <td> </td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td> Steven Gerrard\\n Midfield — Liverpool</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 20</td>\n",
       "      <td> 5</td>\n",
       "      <td>  1</td>\n",
       "      <td> 11</td>\n",
       "      <td>  7.50</td>\n",
       "      <td> 150.01</td>\n",
       "      <td> </td>\n",
       "      <td> </td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "                                  player salary  games  goals  assists  \\\n",
       "7     Cesc Fàbregas\\n Midfield — Chelsea   14.0     20      2       14   \n",
       "8   Saido Berahino\\n Forward — West Brom   13.8     21      9        0   \n",
       "9  Steven Gerrard\\n Midfield — Liverpool   13.8     20      5        1   \n",
       "\n",
       "   shots_on_target  points_per_game  points position team  \n",
       "7               10            10.47  209.49                \n",
       "8               20             7.02  147.43                \n",
       "9               11             7.50  150.01                "
      ]
     },
     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df['team'] = pd.Series('', index=df.index)\n",
    "\n",
    "# or\n",
    "df.insert(loc=8, column='position', value='') \n",
    "\n",
    "df.tail(3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>  Cesc Fàbregas</td>\n",
       "      <td> 14.0</td>\n",
       "      <td> 20</td>\n",
       "      <td> 2</td>\n",
       "      <td> 14</td>\n",
       "      <td> 10</td>\n",
       "      <td> 10.47</td>\n",
       "      <td> 209.49</td>\n",
       "      <td> Midfield</td>\n",
       "      <td>   Chelsea</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td> Saido Berahino</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td> 9</td>\n",
       "      <td>  0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "      <td>  Forward</td>\n",
       "      <td> West Brom</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td> Steven Gerrard</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 20</td>\n",
       "      <td> 5</td>\n",
       "      <td>  1</td>\n",
       "      <td> 11</td>\n",
       "      <td>  7.50</td>\n",
       "      <td> 150.01</td>\n",
       "      <td> Midfield</td>\n",
       "      <td> Liverpool</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "           player salary  games  goals  assists  shots_on_target  \\\n",
       "7   Cesc Fàbregas   14.0     20      2       14               10   \n",
       "8  Saido Berahino   13.8     21      9        0               20   \n",
       "9  Steven Gerrard   13.8     20      5        1               11   \n",
       "\n",
       "   points_per_game  points  position       team  \n",
       "7            10.47  209.49  Midfield    Chelsea  \n",
       "8             7.02  147.43   Forward  West Brom  \n",
       "9             7.50  150.01  Midfield  Liverpool  "
      ]
     },
     "execution_count": 7,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Processing `player` column\n",
    "\n",
    "def process_player_col(text):\n",
    "    name, rest = text.split('\\n')\n",
    "    position, team = [x.strip() for x in rest.split(' — ')]\n",
    "    return pd.Series([name, team, position])\n",
    "\n",
    "df[['player', 'team', 'position']] = df.player.apply(process_player_col)\n",
    "\n",
    "# modified after tip from reddit.com/user/hharison\n",
    "#\n",
    "# Alternative (inferior) approach:\n",
    "#\n",
    "#for idx,row in df.iterrows():\n",
    "#    name, position, team = process_player_col(row['player'])\n",
    "#    df.ix[idx, 'player'], df.ix[idx, 'position'], df.ix[idx, 'team'] = name, position, team\n",
    "    \n",
    "df.tail(3)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Applying Functions to Multiple Columns"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>  sergio agüero</td>\n",
       "      <td> 19.2</td>\n",
       "      <td> 16</td>\n",
       "      <td> 14</td>\n",
       "      <td>  3</td>\n",
       "      <td> 34</td>\n",
       "      <td> 13.12</td>\n",
       "      <td> 209.98</td>\n",
       "      <td>  forward</td>\n",
       "      <td>   manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>    eden hazard</td>\n",
       "      <td> 18.9</td>\n",
       "      <td> 21</td>\n",
       "      <td>  8</td>\n",
       "      <td>  4</td>\n",
       "      <td> 17</td>\n",
       "      <td> 13.05</td>\n",
       "      <td> 274.04</td>\n",
       "      <td> midfield</td>\n",
       "      <td>           chelsea</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td> alexis sánchez</td>\n",
       "      <td> 17.6</td>\n",
       "      <td>NaN</td>\n",
       "      <td> 12</td>\n",
       "      <td>  7</td>\n",
       "      <td> 29</td>\n",
       "      <td> 11.19</td>\n",
       "      <td> 223.86</td>\n",
       "      <td>  forward</td>\n",
       "      <td>           arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>     yaya touré</td>\n",
       "      <td> 16.6</td>\n",
       "      <td> 18</td>\n",
       "      <td>  7</td>\n",
       "      <td>  1</td>\n",
       "      <td> 19</td>\n",
       "      <td> 10.99</td>\n",
       "      <td> 197.91</td>\n",
       "      <td> midfield</td>\n",
       "      <td>   manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td> ángel di maría</td>\n",
       "      <td> 15.0</td>\n",
       "      <td> 13</td>\n",
       "      <td>  3</td>\n",
       "      <td>NaN</td>\n",
       "      <td> 13</td>\n",
       "      <td> 10.17</td>\n",
       "      <td> 132.23</td>\n",
       "      <td> midfield</td>\n",
       "      <td> manchester united</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "           player salary  games  goals  assists  shots_on_target  \\\n",
       "0   sergio agüero   19.2     16     14        3               34   \n",
       "1     eden hazard   18.9     21      8        4               17   \n",
       "2  alexis sánchez   17.6    NaN     12        7               29   \n",
       "3      yaya touré   16.6     18      7        1               19   \n",
       "4  ángel di maría   15.0     13      3      NaN               13   \n",
       "\n",
       "   points_per_game  points  position               team  \n",
       "0            13.12  209.98   forward    manchester city  \n",
       "1            13.05  274.04  midfield            chelsea  \n",
       "2            11.19  223.86   forward            arsenal  \n",
       "3            10.99  197.91  midfield    manchester city  \n",
       "4            10.17  132.23  midfield  manchester united  "
      ]
     },
     "execution_count": 8,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "cols = ['player', 'position', 'team']\n",
    "df[cols] = df[cols].applymap(lambda x: x.lower())\n",
    "df.head()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Missing Values aka NaNs"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "[[back to section overview](#Sections)]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Counting Rows with NaNs"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "3 rows have missing values\n"
     ]
    }
   ],
   "source": [
    "nans = df.shape[0] - df.dropna().shape[0]\n",
    "\n",
    "print('%d rows have missing values' % nans)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Selecting NaN Rows"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>   ángel di maría</td>\n",
       "      <td> 15.0</td>\n",
       "      <td> 13</td>\n",
       "      <td> 3</td>\n",
       "      <td>NaN</td>\n",
       "      <td> 13</td>\n",
       "      <td> 10.17</td>\n",
       "      <td> 132.23</td>\n",
       "      <td> midfield</td>\n",
       "      <td> manchester united</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td> santiago cazorla</td>\n",
       "      <td> 14.8</td>\n",
       "      <td> 20</td>\n",
       "      <td> 4</td>\n",
       "      <td>NaN</td>\n",
       "      <td> 20</td>\n",
       "      <td>  9.97</td>\n",
       "      <td>    NaN</td>\n",
       "      <td> midfield</td>\n",
       "      <td>           arsenal</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "             player salary  games  goals  assists  shots_on_target  \\\n",
       "4    ángel di maría   15.0     13      3      NaN               13   \n",
       "5  santiago cazorla   14.8     20      4      NaN               20   \n",
       "\n",
       "   points_per_game  points  position               team  \n",
       "4            10.17  132.23  midfield  manchester united  \n",
       "5             9.97     NaN  midfield            arsenal  "
      ]
     },
     "execution_count": 10,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Selecting all rows that have NaNs in the `assists` column\n",
    "\n",
    "df[df['assists'].isnull()]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Selecting non-NaN Rows"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>  sergio agüero</td>\n",
       "      <td> 19.2</td>\n",
       "      <td> 16</td>\n",
       "      <td> 14</td>\n",
       "      <td>  3</td>\n",
       "      <td> 34</td>\n",
       "      <td> 13.12</td>\n",
       "      <td> 209.98</td>\n",
       "      <td>  forward</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>    eden hazard</td>\n",
       "      <td> 18.9</td>\n",
       "      <td> 21</td>\n",
       "      <td>  8</td>\n",
       "      <td>  4</td>\n",
       "      <td> 17</td>\n",
       "      <td> 13.05</td>\n",
       "      <td> 274.04</td>\n",
       "      <td> midfield</td>\n",
       "      <td>         chelsea</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td> alexis sánchez</td>\n",
       "      <td> 17.6</td>\n",
       "      <td>NaN</td>\n",
       "      <td> 12</td>\n",
       "      <td>  7</td>\n",
       "      <td> 29</td>\n",
       "      <td> 11.19</td>\n",
       "      <td> 223.86</td>\n",
       "      <td>  forward</td>\n",
       "      <td>         arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>     yaya touré</td>\n",
       "      <td> 16.6</td>\n",
       "      <td> 18</td>\n",
       "      <td>  7</td>\n",
       "      <td>  1</td>\n",
       "      <td> 19</td>\n",
       "      <td> 10.99</td>\n",
       "      <td> 197.91</td>\n",
       "      <td> midfield</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>    david silva</td>\n",
       "      <td> 14.3</td>\n",
       "      <td> 15</td>\n",
       "      <td>  6</td>\n",
       "      <td>  2</td>\n",
       "      <td> 11</td>\n",
       "      <td> 10.35</td>\n",
       "      <td> 155.26</td>\n",
       "      <td> midfield</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>  cesc fàbregas</td>\n",
       "      <td> 14.0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  2</td>\n",
       "      <td> 14</td>\n",
       "      <td> 10</td>\n",
       "      <td> 10.47</td>\n",
       "      <td> 209.49</td>\n",
       "      <td> midfield</td>\n",
       "      <td>         chelsea</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td> saido berahino</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td>  9</td>\n",
       "      <td>  0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "      <td>  forward</td>\n",
       "      <td>       west brom</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td> steven gerrard</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 20</td>\n",
       "      <td>  5</td>\n",
       "      <td>  1</td>\n",
       "      <td> 11</td>\n",
       "      <td>  7.50</td>\n",
       "      <td> 150.01</td>\n",
       "      <td> midfield</td>\n",
       "      <td>       liverpool</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "           player salary  games  goals  assists  shots_on_target  \\\n",
       "0   sergio agüero   19.2     16     14        3               34   \n",
       "1     eden hazard   18.9     21      8        4               17   \n",
       "2  alexis sánchez   17.6    NaN     12        7               29   \n",
       "3      yaya touré   16.6     18      7        1               19   \n",
       "6     david silva   14.3     15      6        2               11   \n",
       "7   cesc fàbregas   14.0     20      2       14               10   \n",
       "8  saido berahino   13.8     21      9        0               20   \n",
       "9  steven gerrard   13.8     20      5        1               11   \n",
       "\n",
       "   points_per_game  points  position             team  \n",
       "0            13.12  209.98   forward  manchester city  \n",
       "1            13.05  274.04  midfield          chelsea  \n",
       "2            11.19  223.86   forward          arsenal  \n",
       "3            10.99  197.91  midfield  manchester city  \n",
       "6            10.35  155.26  midfield  manchester city  \n",
       "7            10.47  209.49  midfield          chelsea  \n",
       "8             7.02  147.43   forward        west brom  \n",
       "9             7.50  150.01  midfield        liverpool  "
      ]
     },
     "execution_count": 11,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df[df['assists'].notnull()]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Filling NaN Rows"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>    sergio agüero</td>\n",
       "      <td> 19.2</td>\n",
       "      <td> 16</td>\n",
       "      <td> 14</td>\n",
       "      <td>  3</td>\n",
       "      <td> 34</td>\n",
       "      <td> 13.12</td>\n",
       "      <td> 209.98</td>\n",
       "      <td>  forward</td>\n",
       "      <td>   manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>      eden hazard</td>\n",
       "      <td> 18.9</td>\n",
       "      <td> 21</td>\n",
       "      <td>  8</td>\n",
       "      <td>  4</td>\n",
       "      <td> 17</td>\n",
       "      <td> 13.05</td>\n",
       "      <td> 274.04</td>\n",
       "      <td> midfield</td>\n",
       "      <td>           chelsea</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>   alexis sánchez</td>\n",
       "      <td> 17.6</td>\n",
       "      <td>  0</td>\n",
       "      <td> 12</td>\n",
       "      <td>  7</td>\n",
       "      <td> 29</td>\n",
       "      <td> 11.19</td>\n",
       "      <td> 223.86</td>\n",
       "      <td>  forward</td>\n",
       "      <td>           arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>       yaya touré</td>\n",
       "      <td> 16.6</td>\n",
       "      <td> 18</td>\n",
       "      <td>  7</td>\n",
       "      <td>  1</td>\n",
       "      <td> 19</td>\n",
       "      <td> 10.99</td>\n",
       "      <td> 197.91</td>\n",
       "      <td> midfield</td>\n",
       "      <td>   manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>   ángel di maría</td>\n",
       "      <td> 15.0</td>\n",
       "      <td> 13</td>\n",
       "      <td>  3</td>\n",
       "      <td>  0</td>\n",
       "      <td> 13</td>\n",
       "      <td> 10.17</td>\n",
       "      <td> 132.23</td>\n",
       "      <td> midfield</td>\n",
       "      <td> manchester united</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td> santiago cazorla</td>\n",
       "      <td> 14.8</td>\n",
       "      <td> 20</td>\n",
       "      <td>  4</td>\n",
       "      <td>  0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  9.97</td>\n",
       "      <td>   0.00</td>\n",
       "      <td> midfield</td>\n",
       "      <td>           arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>      david silva</td>\n",
       "      <td> 14.3</td>\n",
       "      <td> 15</td>\n",
       "      <td>  6</td>\n",
       "      <td>  2</td>\n",
       "      <td> 11</td>\n",
       "      <td> 10.35</td>\n",
       "      <td> 155.26</td>\n",
       "      <td> midfield</td>\n",
       "      <td>   manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td>    cesc fàbregas</td>\n",
       "      <td> 14.0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  2</td>\n",
       "      <td> 14</td>\n",
       "      <td> 10</td>\n",
       "      <td> 10.47</td>\n",
       "      <td> 209.49</td>\n",
       "      <td> midfield</td>\n",
       "      <td>           chelsea</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td>   saido berahino</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td>  9</td>\n",
       "      <td>  0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "      <td>  forward</td>\n",
       "      <td>         west brom</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>   steven gerrard</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 20</td>\n",
       "      <td>  5</td>\n",
       "      <td>  1</td>\n",
       "      <td> 11</td>\n",
       "      <td>  7.50</td>\n",
       "      <td> 150.01</td>\n",
       "      <td> midfield</td>\n",
       "      <td>         liverpool</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "             player salary  games  goals  assists  shots_on_target  \\\n",
       "0     sergio agüero   19.2     16     14        3               34   \n",
       "1       eden hazard   18.9     21      8        4               17   \n",
       "2    alexis sánchez   17.6      0     12        7               29   \n",
       "3        yaya touré   16.6     18      7        1               19   \n",
       "4    ángel di maría   15.0     13      3        0               13   \n",
       "5  santiago cazorla   14.8     20      4        0               20   \n",
       "6       david silva   14.3     15      6        2               11   \n",
       "7     cesc fàbregas   14.0     20      2       14               10   \n",
       "8    saido berahino   13.8     21      9        0               20   \n",
       "9    steven gerrard   13.8     20      5        1               11   \n",
       "\n",
       "   points_per_game  points  position               team  \n",
       "0            13.12  209.98   forward    manchester city  \n",
       "1            13.05  274.04  midfield            chelsea  \n",
       "2            11.19  223.86   forward            arsenal  \n",
       "3            10.99  197.91  midfield    manchester city  \n",
       "4            10.17  132.23  midfield  manchester united  \n",
       "5             9.97    0.00  midfield            arsenal  \n",
       "6            10.35  155.26  midfield    manchester city  \n",
       "7            10.47  209.49  midfield            chelsea  \n",
       "8             7.02  147.43   forward          west brom  \n",
       "9             7.50  150.01  midfield          liverpool  "
      ]
     },
     "execution_count": 12,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Filling NaN cells with default value 0\n",
    "\n",
    "df.fillna(value=0, inplace=True)\n",
    "df"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Appending Rows to a DataFrame"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "[[back to section overview](#Sections)]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>8 </th>\n",
       "      <td> saido berahino</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td>  9</td>\n",
       "      <td>  0</td>\n",
       "      <td> 20</td>\n",
       "      <td> 7.02</td>\n",
       "      <td> 147.43</td>\n",
       "      <td>  forward</td>\n",
       "      <td> west brom</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9 </th>\n",
       "      <td> steven gerrard</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 20</td>\n",
       "      <td>  5</td>\n",
       "      <td>  1</td>\n",
       "      <td> 11</td>\n",
       "      <td> 7.50</td>\n",
       "      <td> 150.01</td>\n",
       "      <td> midfield</td>\n",
       "      <td> liverpool</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>            NaN</td>\n",
       "      <td>  NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>  NaN</td>\n",
       "      <td>    NaN</td>\n",
       "      <td>      NaN</td>\n",
       "      <td>       NaN</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "            player salary  games  goals  assists  shots_on_target  \\\n",
       "8   saido berahino   13.8     21      9        0               20   \n",
       "9   steven gerrard   13.8     20      5        1               11   \n",
       "10             NaN    NaN    NaN    NaN      NaN              NaN   \n",
       "\n",
       "    points_per_game  points  position       team  \n",
       "8              7.02  147.43   forward  west brom  \n",
       "9              7.50  150.01  midfield  liverpool  \n",
       "10              NaN     NaN       NaN        NaN  "
      ]
     },
     "execution_count": 13,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Adding an \"empty\" row to the DataFrame\n",
    "\n",
    "import numpy as np\n",
    "\n",
    "df = df.append(pd.Series(\n",
    "                [np.nan]*len(df.columns), # Fill cells with NaNs\n",
    "                index=df.columns),    \n",
    "                ignore_index=True)\n",
    "\n",
    "df.tail(3)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>8 </th>\n",
       "      <td> saido berahino</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td>  9</td>\n",
       "      <td>  0</td>\n",
       "      <td> 20</td>\n",
       "      <td> 7.02</td>\n",
       "      <td> 147.43</td>\n",
       "      <td>  forward</td>\n",
       "      <td> west brom</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9 </th>\n",
       "      <td> steven gerrard</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 20</td>\n",
       "      <td>  5</td>\n",
       "      <td>  1</td>\n",
       "      <td> 11</td>\n",
       "      <td> 7.50</td>\n",
       "      <td> 150.01</td>\n",
       "      <td> midfield</td>\n",
       "      <td> liverpool</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>10</th>\n",
       "      <td>     new player</td>\n",
       "      <td> 12.3</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>  NaN</td>\n",
       "      <td>    NaN</td>\n",
       "      <td>      NaN</td>\n",
       "      <td>       NaN</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "            player salary  games  goals  assists  shots_on_target  \\\n",
       "8   saido berahino   13.8     21      9        0               20   \n",
       "9   steven gerrard   13.8     20      5        1               11   \n",
       "10      new player   12.3    NaN    NaN      NaN              NaN   \n",
       "\n",
       "    points_per_game  points  position       team  \n",
       "8              7.02  147.43   forward  west brom  \n",
       "9              7.50  150.01  midfield  liverpool  \n",
       "10              NaN     NaN       NaN        NaN  "
      ]
     },
     "execution_count": 14,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Filling cells with data\n",
    "\n",
    "df.loc[df.index[-1], 'player'] = 'new player'\n",
    "df.loc[df.index[-1], 'salary'] = 12.3\n",
    "df.tail(3)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Sorting and Reindexing DataFrames"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "[[back to section overview](#Sections)]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>  sergio agüero</td>\n",
       "      <td> 19.2</td>\n",
       "      <td> 16</td>\n",
       "      <td> 14</td>\n",
       "      <td> 3</td>\n",
       "      <td> 34</td>\n",
       "      <td> 13.12</td>\n",
       "      <td> 209.98</td>\n",
       "      <td>  forward</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td> alexis sánchez</td>\n",
       "      <td> 17.6</td>\n",
       "      <td>  0</td>\n",
       "      <td> 12</td>\n",
       "      <td> 7</td>\n",
       "      <td> 29</td>\n",
       "      <td> 11.19</td>\n",
       "      <td> 223.86</td>\n",
       "      <td>  forward</td>\n",
       "      <td>         arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>8</th>\n",
       "      <td> saido berahino</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td>  9</td>\n",
       "      <td> 0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "      <td>  forward</td>\n",
       "      <td>       west brom</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>    eden hazard</td>\n",
       "      <td> 18.9</td>\n",
       "      <td> 21</td>\n",
       "      <td>  8</td>\n",
       "      <td> 4</td>\n",
       "      <td> 17</td>\n",
       "      <td> 13.05</td>\n",
       "      <td> 274.04</td>\n",
       "      <td> midfield</td>\n",
       "      <td>         chelsea</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>     yaya touré</td>\n",
       "      <td> 16.6</td>\n",
       "      <td> 18</td>\n",
       "      <td>  7</td>\n",
       "      <td> 1</td>\n",
       "      <td> 19</td>\n",
       "      <td> 10.99</td>\n",
       "      <td> 197.91</td>\n",
       "      <td> midfield</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "           player salary  games  goals  assists  shots_on_target  \\\n",
       "0   sergio agüero   19.2     16     14        3               34   \n",
       "2  alexis sánchez   17.6      0     12        7               29   \n",
       "8  saido berahino   13.8     21      9        0               20   \n",
       "1     eden hazard   18.9     21      8        4               17   \n",
       "3      yaya touré   16.6     18      7        1               19   \n",
       "\n",
       "   points_per_game  points  position             team  \n",
       "0            13.12  209.98   forward  manchester city  \n",
       "2            11.19  223.86   forward          arsenal  \n",
       "8             7.02  147.43   forward        west brom  \n",
       "1            13.05  274.04  midfield          chelsea  \n",
       "3            10.99  197.91  midfield  manchester city  "
      ]
     },
     "execution_count": 15,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Sorting the DataFrame by a certain column (from highest to lowest)\n",
    "\n",
    "df.sort('goals', ascending=False, inplace=True)\n",
    "df.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>  sergio agüero</td>\n",
       "      <td> 19.2</td>\n",
       "      <td> 16</td>\n",
       "      <td> 14</td>\n",
       "      <td> 3</td>\n",
       "      <td> 34</td>\n",
       "      <td> 13.12</td>\n",
       "      <td> 209.98</td>\n",
       "      <td>  forward</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td> alexis sánchez</td>\n",
       "      <td> 17.6</td>\n",
       "      <td>  0</td>\n",
       "      <td> 12</td>\n",
       "      <td> 7</td>\n",
       "      <td> 29</td>\n",
       "      <td> 11.19</td>\n",
       "      <td> 223.86</td>\n",
       "      <td>  forward</td>\n",
       "      <td>         arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td> saido berahino</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td>  9</td>\n",
       "      <td> 0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "      <td>  forward</td>\n",
       "      <td>       west brom</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>    eden hazard</td>\n",
       "      <td> 18.9</td>\n",
       "      <td> 21</td>\n",
       "      <td>  8</td>\n",
       "      <td> 4</td>\n",
       "      <td> 17</td>\n",
       "      <td> 13.05</td>\n",
       "      <td> 274.04</td>\n",
       "      <td> midfield</td>\n",
       "      <td>         chelsea</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>     yaya touré</td>\n",
       "      <td> 16.6</td>\n",
       "      <td> 18</td>\n",
       "      <td>  7</td>\n",
       "      <td> 1</td>\n",
       "      <td> 19</td>\n",
       "      <td> 10.99</td>\n",
       "      <td> 197.91</td>\n",
       "      <td> midfield</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "           player salary  games  goals  assists  shots_on_target  \\\n",
       "1   sergio agüero   19.2     16     14        3               34   \n",
       "2  alexis sánchez   17.6      0     12        7               29   \n",
       "3  saido berahino   13.8     21      9        0               20   \n",
       "4     eden hazard   18.9     21      8        4               17   \n",
       "5      yaya touré   16.6     18      7        1               19   \n",
       "\n",
       "   points_per_game  points  position             team  \n",
       "1            13.12  209.98   forward  manchester city  \n",
       "2            11.19  223.86   forward          arsenal  \n",
       "3             7.02  147.43   forward        west brom  \n",
       "4            13.05  274.04  midfield          chelsea  \n",
       "5            10.99  197.91  midfield  manchester city  "
      ]
     },
     "execution_count": 16,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Optional reindexing of the DataFrame after sorting\n",
    "\n",
    "df.index = range(1,len(df.index)+1)\n",
    "df.head()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Updating Columns"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "[[back to section overview](#Sections)]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>  sergio agüero</td>\n",
       "      <td>   20</td>\n",
       "      <td> 16</td>\n",
       "      <td> 14</td>\n",
       "      <td> 3</td>\n",
       "      <td> 34</td>\n",
       "      <td> 13.12</td>\n",
       "      <td> 209.98</td>\n",
       "      <td> forward</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td> alexis sánchez</td>\n",
       "      <td>   15</td>\n",
       "      <td>  0</td>\n",
       "      <td> 12</td>\n",
       "      <td> 7</td>\n",
       "      <td> 29</td>\n",
       "      <td> 11.19</td>\n",
       "      <td> 223.86</td>\n",
       "      <td> forward</td>\n",
       "      <td>         arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td> saido berahino</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td>  9</td>\n",
       "      <td> 0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "      <td> forward</td>\n",
       "      <td>       west brom</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "           player salary  games  goals  assists  shots_on_target  \\\n",
       "1   sergio agüero     20     16     14        3               34   \n",
       "2  alexis sánchez     15      0     12        7               29   \n",
       "3  saido berahino   13.8     21      9        0               20   \n",
       "\n",
       "   points_per_game  points position             team  \n",
       "1            13.12  209.98  forward  manchester city  \n",
       "2            11.19  223.86  forward          arsenal  \n",
       "3             7.02  147.43  forward        west brom  "
      ]
     },
     "execution_count": 17,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Creating a dummy DataFrame with changes in the `salary` column\n",
    "\n",
    "df_2 = df.copy()\n",
    "df_2.loc[0:2, 'salary'] = [20.0, 15.0]\n",
    "df_2.head(3)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>player</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>sergio agüero</th>\n",
       "      <td> 19.2</td>\n",
       "      <td> 16</td>\n",
       "      <td> 14</td>\n",
       "      <td> 3</td>\n",
       "      <td> 34</td>\n",
       "      <td> 13.12</td>\n",
       "      <td> 209.98</td>\n",
       "      <td> forward</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>alexis sánchez</th>\n",
       "      <td> 17.6</td>\n",
       "      <td>  0</td>\n",
       "      <td> 12</td>\n",
       "      <td> 7</td>\n",
       "      <td> 29</td>\n",
       "      <td> 11.19</td>\n",
       "      <td> 223.86</td>\n",
       "      <td> forward</td>\n",
       "      <td>         arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>saido berahino</th>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td>  9</td>\n",
       "      <td> 0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "      <td> forward</td>\n",
       "      <td>       west brom</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "               salary  games  goals  assists  shots_on_target  \\\n",
       "player                                                          \n",
       "sergio agüero    19.2     16     14        3               34   \n",
       "alexis sánchez   17.6      0     12        7               29   \n",
       "saido berahino   13.8     21      9        0               20   \n",
       "\n",
       "                points_per_game  points position             team  \n",
       "player                                                             \n",
       "sergio agüero             13.12  209.98  forward  manchester city  \n",
       "alexis sánchez            11.19  223.86  forward          arsenal  \n",
       "saido berahino             7.02  147.43  forward        west brom  "
      ]
     },
     "execution_count": 18,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Temporarily use the `player` columns as indices to \n",
    "# apply the update functions\n",
    "\n",
    "df.set_index('player', inplace=True)\n",
    "df_2.set_index('player', inplace=True)\n",
    "df.head(3)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>player</th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "      <th></th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>sergio agüero</th>\n",
       "      <td>   20</td>\n",
       "      <td> 16</td>\n",
       "      <td> 14</td>\n",
       "      <td> 3</td>\n",
       "      <td> 34</td>\n",
       "      <td> 13.12</td>\n",
       "      <td> 209.98</td>\n",
       "      <td> forward</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>alexis sánchez</th>\n",
       "      <td>   15</td>\n",
       "      <td>  0</td>\n",
       "      <td> 12</td>\n",
       "      <td> 7</td>\n",
       "      <td> 29</td>\n",
       "      <td> 11.19</td>\n",
       "      <td> 223.86</td>\n",
       "      <td> forward</td>\n",
       "      <td>         arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>saido berahino</th>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td>  9</td>\n",
       "      <td> 0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "      <td> forward</td>\n",
       "      <td>       west brom</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "               salary  games  goals  assists  shots_on_target  \\\n",
       "player                                                          \n",
       "sergio agüero      20     16     14        3               34   \n",
       "alexis sánchez     15      0     12        7               29   \n",
       "saido berahino   13.8     21      9        0               20   \n",
       "\n",
       "                points_per_game  points position             team  \n",
       "player                                                             \n",
       "sergio agüero             13.12  209.98  forward  manchester city  \n",
       "alexis sánchez            11.19  223.86  forward          arsenal  \n",
       "saido berahino             7.02  147.43  forward        west brom  "
      ]
     },
     "execution_count": 19,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Update the `salary` column\n",
    "df.update(other=df_2['salary'], overwrite=True)\n",
    "df.head(3)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>  sergio agüero</td>\n",
       "      <td>   20</td>\n",
       "      <td> 16</td>\n",
       "      <td> 14</td>\n",
       "      <td> 3</td>\n",
       "      <td> 34</td>\n",
       "      <td> 13.12</td>\n",
       "      <td> 209.98</td>\n",
       "      <td> forward</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td> alexis sánchez</td>\n",
       "      <td>   15</td>\n",
       "      <td>  0</td>\n",
       "      <td> 12</td>\n",
       "      <td> 7</td>\n",
       "      <td> 29</td>\n",
       "      <td> 11.19</td>\n",
       "      <td> 223.86</td>\n",
       "      <td> forward</td>\n",
       "      <td>         arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td> saido berahino</td>\n",
       "      <td> 13.8</td>\n",
       "      <td> 21</td>\n",
       "      <td>  9</td>\n",
       "      <td> 0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  7.02</td>\n",
       "      <td> 147.43</td>\n",
       "      <td> forward</td>\n",
       "      <td>       west brom</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "           player salary  games  goals  assists  shots_on_target  \\\n",
       "0   sergio agüero     20     16     14        3               34   \n",
       "1  alexis sánchez     15      0     12        7               29   \n",
       "2  saido berahino   13.8     21      9        0               20   \n",
       "\n",
       "   points_per_game  points position             team  \n",
       "0            13.12  209.98  forward  manchester city  \n",
       "1            11.19  223.86  forward          arsenal  \n",
       "2             7.02  147.43  forward        west brom  "
      ]
     },
     "execution_count": 20,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Reset the indices\n",
    "df.reset_index(inplace=True)\n",
    "df.head(3)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Chaining Conditions - Using Bitwise Operators"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "[[back to section overview](#Sections)]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>   alexis sánchez</td>\n",
       "      <td>   15</td>\n",
       "      <td>  0</td>\n",
       "      <td> 12</td>\n",
       "      <td>  7</td>\n",
       "      <td> 29</td>\n",
       "      <td> 11.19</td>\n",
       "      <td> 223.86</td>\n",
       "      <td>  forward</td>\n",
       "      <td> arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>      eden hazard</td>\n",
       "      <td> 18.9</td>\n",
       "      <td> 21</td>\n",
       "      <td>  8</td>\n",
       "      <td>  4</td>\n",
       "      <td> 17</td>\n",
       "      <td> 13.05</td>\n",
       "      <td> 274.04</td>\n",
       "      <td> midfield</td>\n",
       "      <td> chelsea</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>7</th>\n",
       "      <td> santiago cazorla</td>\n",
       "      <td> 14.8</td>\n",
       "      <td> 20</td>\n",
       "      <td>  4</td>\n",
       "      <td>  0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  9.97</td>\n",
       "      <td>   0.00</td>\n",
       "      <td> midfield</td>\n",
       "      <td> arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9</th>\n",
       "      <td>    cesc fàbregas</td>\n",
       "      <td> 14.0</td>\n",
       "      <td> 20</td>\n",
       "      <td>  2</td>\n",
       "      <td> 14</td>\n",
       "      <td> 10</td>\n",
       "      <td> 10.47</td>\n",
       "      <td> 209.49</td>\n",
       "      <td> midfield</td>\n",
       "      <td> chelsea</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "             player salary  games  goals  assists  shots_on_target  \\\n",
       "1    alexis sánchez     15      0     12        7               29   \n",
       "3       eden hazard   18.9     21      8        4               17   \n",
       "7  santiago cazorla   14.8     20      4        0               20   \n",
       "9     cesc fàbregas   14.0     20      2       14               10   \n",
       "\n",
       "   points_per_game  points  position     team  \n",
       "1            11.19  223.86   forward  arsenal  \n",
       "3            13.05  274.04  midfield  chelsea  \n",
       "7             9.97    0.00  midfield  arsenal  \n",
       "9            10.47  209.49  midfield  chelsea  "
      ]
     },
     "execution_count": 21,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Selecting only those players that either playing for Arsenal or Chelsea\n",
    "\n",
    "df[ (df['team'] == 'arsenal') | (df['team'] == 'chelsea') ]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 22,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>games</th>\n",
       "      <th>goals</th>\n",
       "      <th>assists</th>\n",
       "      <th>shots_on_target</th>\n",
       "      <th>points_per_game</th>\n",
       "      <th>points</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td> alexis sánchez</td>\n",
       "      <td> 15</td>\n",
       "      <td> 0</td>\n",
       "      <td> 12</td>\n",
       "      <td> 7</td>\n",
       "      <td> 29</td>\n",
       "      <td> 11.19</td>\n",
       "      <td> 223.86</td>\n",
       "      <td> forward</td>\n",
       "      <td> arsenal</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "           player salary  games  goals  assists  shots_on_target  \\\n",
       "1  alexis sánchez     15      0     12        7               29   \n",
       "\n",
       "   points_per_game  points position     team  \n",
       "1            11.19  223.86  forward  arsenal  "
      ]
     },
     "execution_count": 22,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Selecting forwards from Arsenal only\n",
    "\n",
    "df[ (df['team'] == 'arsenal') & (df['position'] == 'forward') ]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Column Types"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "[[back to section overview](#Sections)]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Printing Column Types"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 23,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "{dtype('float64'): ['games',\n",
       "  'goals',\n",
       "  'assists',\n",
       "  'shots_on_target',\n",
       "  'points_per_game',\n",
       "  'points'],\n",
       " dtype('O'): ['player', 'salary', 'position', 'team']}"
      ]
     },
     "execution_count": 23,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "types = df.columns.to_series().groupby(df.dtypes).groups\n",
    "types"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Selecting by Column Type"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 24,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "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>player</th>\n",
       "      <th>salary</th>\n",
       "      <th>position</th>\n",
       "      <th>team</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>  sergio agüero</td>\n",
       "      <td>   20</td>\n",
       "      <td>  forward</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td> alexis sánchez</td>\n",
       "      <td>   15</td>\n",
       "      <td>  forward</td>\n",
       "      <td>         arsenal</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td> saido berahino</td>\n",
       "      <td> 13.8</td>\n",
       "      <td>  forward</td>\n",
       "      <td>       west brom</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>    eden hazard</td>\n",
       "      <td> 18.9</td>\n",
       "      <td> midfield</td>\n",
       "      <td>         chelsea</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>     yaya touré</td>\n",
       "      <td> 16.6</td>\n",
       "      <td> midfield</td>\n",
       "      <td> manchester city</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "           player salary  position             team\n",
       "0   sergio agüero     20   forward  manchester city\n",
       "1  alexis sánchez     15   forward          arsenal\n",
       "2  saido berahino   13.8   forward        west brom\n",
       "3     eden hazard   18.9  midfield          chelsea\n",
       "4      yaya touré   16.6  midfield  manchester city"
      ]
     },
     "execution_count": 24,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# select string columns\n",
    "df.loc[:, (df.dtypes == np.dtype('O')).values].head()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Converting Column Types"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 25,
   "metadata": {
    "collapsed": false
   },
   "outputs": [],
   "source": [
    "df['salary'] = df['salary'].astype(float)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 26,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "{dtype('float64'): ['salary',\n",
       "  'games',\n",
       "  'goals',\n",
       "  'assists',\n",
       "  'shots_on_target',\n",
       "  'points_per_game',\n",
       "  'points'],\n",
       " dtype('O'): ['player', 'position', 'team']}"
      ]
     },
     "execution_count": 26,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "types = df.columns.to_series().groupby(df.dtypes).groups\n",
    "types"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<br>\n",
    "<br>"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# If-tests"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "[[back to section overview](#Sections)]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "I was recently asked how to do an if-test in pandas, that is, how to create an array of 1s and 0s depending on a condition, e.g., if `val` less than 0.5 -> 0, else -> 1. Using the boolean mask, that's pretty simple since `True` and `False` are integers after all."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/plain": [
       "1"
      ]
     },
     "execution_count": 1,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "int(True)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>0</th>\n",
       "      <th>1</th>\n",
       "      <th>2</th>\n",
       "      <th>3</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>2.0</td>\n",
       "      <td>0.30</td>\n",
       "      <td>4.00</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>0.8</td>\n",
       "      <td>0.03</td>\n",
       "      <td>0.02</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     0     1     2  3\n",
       "0  2.0  0.30  4.00  5\n",
       "1  0.8  0.03  0.02  5"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import pandas as pd\n",
    "\n",
    "a = [[2., .3, 4., 5.], [.8, .03, 0.02, 5.]]\n",
    "df = pd.DataFrame(a)\n",
    "df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>0</th>\n",
       "      <th>1</th>\n",
       "      <th>2</th>\n",
       "      <th>3</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "      <td>False</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>False</td>\n",
       "      <td>True</td>\n",
       "      <td>True</td>\n",
       "      <td>False</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "       0      1      2      3\n",
       "0  False  False  False  False\n",
       "1  False   True   True  False"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df = df <= 0.05\n",
    "df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>0</th>\n",
       "      <th>1</th>\n",
       "      <th>2</th>\n",
       "      <th>3</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "      <td>0</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>0</td>\n",
       "      <td>1</td>\n",
       "      <td>1</td>\n",
       "      <td>0</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   0  1  2  3\n",
       "0  0  0  0  0\n",
       "1  0  1  1  0"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.astype(int)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": []
  }
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   "display_name": "Python 3",
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   "codemirror_mode": {
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