Pandas.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Pandas\n",
    "One of the best options for working with tabular data in Python is to use the Python Data Analysis Library (a.k.a. Pandas). The Pandas library provides DataFrame data structure, produces high quality plots with matplotlib and integrates nicely with other libraries that use NumPy arrays."
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Here is an example of the data set (gapminder) that is best represented by the DataFrame\n",
    " https://github.com/AnnaWilliford/SWC_Fall2019_test/blob/master/gapminder.txt"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 418,
   "metadata": {},
   "outputs": [],
   "source": [
    "import pandas as pd\n",
    "import numpy as np"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Creating Data Frames: "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 419,
   "metadata": {},
   "outputs": [],
   "source": [
    "#From dictionaries\n",
    "grades={'name':['Amy', 'Mike','Jake','Rose']\n",
    "        ,'status':['sophmore','freshman','junior','freshman']        \n",
    "        ,'hw1':[10,4,9,10]\n",
    "        ,'hw2':[8,6,9,10]\n",
    "        ,'test':[88,79,93,99]}"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 420,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
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       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test\n",
       "0   Amy  sophmore   10    8    88\n",
       "1  Mike  freshman    4    6    79\n",
       "2  Jake    junior    9    9    93\n",
       "3  Rose  freshman   10   10    99"
      ]
     },
     "execution_count": 420,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df=pd.DataFrame(grades)\n",
    "grades_df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 421,
   "metadata": {},
   "outputs": [
    {
     "data": {
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       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
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       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>a</th>\n",
       "      <td>Mia</td>\n",
       "      <td>2</td>\n",
       "      <td>3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>b</th>\n",
       "      <td>Jane</td>\n",
       "      <td>5</td>\n",
       "      <td>6</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name hw1 hw2\n",
       "a   Mia   2   3\n",
       "b  Jane   5   6"
      ]
     },
     "execution_count": 421,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#from numpy arrays\n",
    "df = pd.DataFrame(data=np.array([['Mia', 2, 3], ['Jane', 5, 6]]), index= ['a','b'], columns=['name','hw1','hw2'])\n",
    "df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 422,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "a    23\n",
       "b    56\n",
       "dtype: object"
      ]
     },
     "execution_count": 422,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.hw1+df.hw2"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 423,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "a     5\n",
       "b    11\n",
       "dtype: int64"
      ]
     },
     "execution_count": 423,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.hw1=df.hw1.astype(np.int)\n",
    "df.hw2=df.hw2.astype(np.int)\n",
    "df.hw1+df.hw2"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 424,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
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       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
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       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>a</th>\n",
       "      <td>0</td>\n",
       "      <td>1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>b</th>\n",
       "      <td>2</td>\n",
       "      <td>3</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>c</th>\n",
       "      <td>4</td>\n",
       "      <td>5</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   hw1  hw2\n",
       "a    0    1\n",
       "b    2    3\n",
       "c    4    5"
      ]
     },
     "execution_count": 424,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df2 = pd.DataFrame(data=np.arange(6).reshape(3,2), index= ['a','b','c'], columns=['hw1','hw2'])\n",
    "df2"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 425,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "a    1\n",
       "b    5\n",
       "c    9\n",
       "dtype: int64"
      ]
     },
     "execution_count": 425,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df2.hw1+df2.hw2"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### The structure of the data frame"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 426,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(4, 5)"
      ]
     },
     "execution_count": 426,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df.shape"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "**DataFrame = data + columns + index. You can access each of these components**"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 427,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "array([['Amy', 'sophmore', 10, 8, 88],\n",
       "       ['Mike', 'freshman', 4, 6, 79],\n",
       "       ['Jake', 'junior', 9, 9, 93],\n",
       "       ['Rose', 'freshman', 10, 10, 99]], dtype=object)"
      ]
     },
     "execution_count": 427,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df.values"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 428,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "Index(['name', 'status', 'hw1', 'hw2', 'test'], dtype='object')"
      ]
     },
     "execution_count": 428,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df.columns"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 429,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "RangeIndex(start=0, stop=4, step=1)"
      ]
     },
     "execution_count": 429,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df.index"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Subsetting dataframe:  \n",
    "There are three main options to extract(select) parts of the data frame\n",
    "\n",
    "1. Selecting data by index\n",
    "2. Selecting data by label\n",
    "3. Selecting data by a conditional statment/logical statements"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 430,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
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       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test\n",
       "0   Amy  sophmore   10    8    88\n",
       "1  Mike  freshman    4    6    79\n",
       "2  Jake    junior    9    9    93\n",
       "3  Rose  freshman   10   10    99"
      ]
     },
     "execution_count": 430,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### Select by index  \n",
    "`df.iloc[<row index>, <column index>]`  "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 431,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "10"
      ]
     },
     "execution_count": 431,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#Get a single element\n",
    "grades_df.iloc[0,2]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 432,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0    10\n",
       "1     4\n",
       "2     9\n",
       "3    10\n",
       "Name: hw1, dtype: int64"
      ]
     },
     "execution_count": 432,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#Get column\n",
    "grades_df.iloc[:,2]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 433,
   "metadata": {},
   "outputs": [
    {
     "data": {
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       "<div>\n",
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       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>status</th>\n",
       "      <th>hw2</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>sophmore</td>\n",
       "      <td>8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>freshman</td>\n",
       "      <td>6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     status  hw2\n",
       "0  sophmore    8\n",
       "1  freshman    6\n",
       "2    junior    9\n",
       "3  freshman   10"
      ]
     },
     "execution_count": 433,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#Get multiple columns\n",
    "grades_df.iloc[:,[1,3]]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 328,
   "metadata": {},
   "outputs": [
    {
     "data": {
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       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test\n",
       "0   Amy  sophmore   10    8    88\n",
       "1  Mike  freshman    4    6    79\n",
       "2  Jake    junior    9    9    93\n",
       "3  Rose  freshman   10   10    99"
      ]
     },
     "execution_count": 328,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 434,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "<class 'pandas.core.frame.DataFrame'>\n",
      "<class 'pandas.core.series.Series'>\n"
     ]
    },
    {
     "data": {
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       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
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      "text/plain": [
       "   name  status  hw1\n",
       "2  Jake  junior    9"
      ]
     },
     "execution_count": 434,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#select rows and columns\n",
    "grades_df.iloc[[2],0:3]\n",
    "\n",
    "#here index of the third row is given in a list, this keeps output as a dataframe\n",
    "print(type(grades_df.iloc[[2],0:3]))\n",
    "print(type(grades_df.iloc[2,0:3]))\n",
    "\n",
    "grades_df.iloc[[2],0:3]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 435,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name  status  hw1  hw2  test\n",
       "2  Jake  junior    9    9    93"
      ]
     },
     "execution_count": 435,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#get a row\n",
    "grades_df.iloc[[2],:]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 437,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test\n",
       "0   Amy  sophmore   10    8    88\n",
       "1  Mike  freshman    4    6    79\n",
       "2  Jake    junior    9    9    93"
      ]
     },
     "execution_count": 437,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#get multiple rows\n",
    "grades_df.iloc[0:3,:]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### Select by label:  \n",
    "`df.loc[<row label>, <column label>]`  \n",
    "or:  \n",
    "`df[<column label>]`  \n",
    "or:\n",
    "`df.<column label>`\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 438,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test\n",
       "0   Amy  sophmore   10    8    88\n",
       "1  Mike  freshman    4    6    79\n",
       "2  Jake    junior    9    9    93\n",
       "3  Rose  freshman   10   10    99"
      ]
     },
     "execution_count": 438,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 439,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0    10\n",
       "1     4\n",
       "2     9\n",
       "3    10\n",
       "Name: hw1, dtype: int64"
      ]
     },
     "execution_count": 439,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df.loc[:,'hw1']"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 440,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   hw1  hw2\n",
       "1    4    6\n",
       "2    9    9\n",
       "3   10   10"
      ]
     },
     "execution_count": 440,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df.loc[1:3,['hw1','hw2']]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Challenge\n",
    "Explain the difference in the output of these two commands:  \n",
    "`grades_df.loc[1:3,:]`  \n",
    "and  \n",
    "`grades_df.iloc[1:3,:]`  "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 441,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>st1</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>st2</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>st3</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>st4</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     name    status  hw1  hw2  test\n",
       "st1   Amy  sophmore   10    8    88\n",
       "st2  Mike  freshman    4    6    79\n",
       "st3  Jake    junior    9    9    93\n",
       "st4  Rose  freshman   10   10    99"
      ]
     },
     "execution_count": 441,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#We can change index\n",
    "grades_df.index=['st1','st2','st3','st4']\n",
    "grades_df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 442,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>st1</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "    name    status  hw1  hw2  test\n",
       "st1  Amy  sophmore   10    8    88"
      ]
     },
     "execution_count": 442,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df.loc[['st1']]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 443,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test\n",
       "0   Amy  sophmore   10    8    88\n",
       "1  Mike  freshman    4    6    79\n",
       "2  Jake    junior    9    9    93\n",
       "3  Rose  freshman   10   10    99"
      ]
     },
     "execution_count": 443,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#reset index  creates new data frame\n",
    "#This comes handy when index is needed to be used as a column.\n",
    "grades_df=grades_df.reset_index(drop=True)\n",
    "grades_df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 444,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0     Amy\n",
       "1    Mike\n",
       "2    Jake\n",
       "3    Rose\n",
       "Name: name, dtype: object"
      ]
     },
     "execution_count": 444,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "### Selecting columns by name\n",
    "# as if dataframe is a dictionary\n",
    "grades_df[['name']]\n",
    "grades_df['name']"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 445,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0     Amy\n",
       "1    Mike\n",
       "2    Jake\n",
       "3    Rose\n",
       "Name: name, dtype: object"
      ]
     },
     "execution_count": 445,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#or using attribute\n",
    "grades_df.name"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "#### Select by logical statement\n",
    "\n",
    "`df.loc[<row selection>, <column selection>]` where row selection is based on logical Pandas series  \n",
    "\n",
    "With logical selection, you pass an array or Series of True/False values to the .loc indexer to select the rows where your Series has True values.\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 446,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test\n",
       "0   Amy  sophmore   10    8    88\n",
       "1  Mike  freshman    4    6    79\n",
       "2  Jake    junior    9    9    93\n",
       "3  Rose  freshman   10   10    99"
      ]
     },
     "execution_count": 446,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 447,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test\n",
       "1  Mike  freshman    4    6    79"
      ]
     },
     "execution_count": 447,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#Select records for Mike\n",
    "grades_df.loc[grades_df['name']=='Mike',]\n",
    "\n",
    "#grades_df['name']=='Mike' identifies row index"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 453,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test\n",
       "1  Mike  freshman    4    6    79"
      ]
     },
     "execution_count": 453,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#or, but this is very confusing...\n",
    "grades_df[grades_df['name']=='Mike']"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 454,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "0    False\n",
       "1     True\n",
       "2    False\n",
       "3    False\n",
       "Name: name, dtype: bool"
      ]
     },
     "execution_count": 454,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df['name']=='Mike'"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "**How it works**  \n",
    "`grades_df['name']=='Mike'` is `True` for index 1.  \n",
    "So  \n",
    "`grades_df.loc[grades_df['name']=='Mike',]`  \n",
    "is the same as  \n",
    "`grades_df.loc[1,]`"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 455,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test\n",
       "1  Mike  freshman    4    6    79"
      ]
     },
     "execution_count": 455,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df.loc[[1],]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 456,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>hw1</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>10</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>10</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name  hw1\n",
       "0   Amy   10\n",
       "2  Jake    9\n",
       "3  Rose   10"
      ]
     },
     "execution_count": 456,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#students with hw1 score more than 7\n",
    "grades_df.loc[grades_df['hw1']>7,['name','hw1']]"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Adding columns and rows"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 459,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test\n",
       "0   Amy  sophmore   10    8    88\n",
       "1  Mike  freshman    4    6    79\n",
       "2  Jake    junior    9    9    93\n",
       "3  Rose  freshman   10   10    99"
      ]
     },
     "execution_count": 459,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 460,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "      <th>hw3</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "      <td>7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "      <td>8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test  hw3\n",
       "0   Amy  sophmore   10    8    88    9\n",
       "1  Mike  freshman    4    6    79    7\n",
       "2  Jake    junior    9    9    93    8\n",
       "3  Rose  freshman   10   10    99    9"
      ]
     },
     "execution_count": 460,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#adding columns\n",
    "grades_df['hw3']=[9,7,8,9]\n",
    "#grades_df.iloc[:,[0,1,2,3,5,4]]\n",
    "grades_df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 461,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
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       "\n",
       "    .dataframe tbody tr th {\n",
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       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "      <th>hw3</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "      <td>7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "      <td>8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>Dan</td>\n",
       "      <td>freshman</td>\n",
       "      <td>3</td>\n",
       "      <td>5</td>\n",
       "      <td>1</td>\n",
       "      <td>50</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test  hw3\n",
       "0   Amy  sophmore   10    8    88    9\n",
       "1  Mike  freshman    4    6    79    7\n",
       "2  Jake    junior    9    9    93    8\n",
       "3  Rose  freshman   10   10    99    9\n",
       "4   Dan  freshman    3    5     1   50"
      ]
     },
     "execution_count": 461,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#adding rows\n",
    "grades_df.loc[4]=['Dan','freshman',3,5,1,50]\n",
    "grades_df"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Deleting rows and columns"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 462,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
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       "\n",
       "    .dataframe tbody tr th {\n",
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       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
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       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>test</th>\n",
       "      <th>hw3</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>88</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>79</td>\n",
       "      <td>7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>93</td>\n",
       "      <td>8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>99</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>Dan</td>\n",
       "      <td>freshman</td>\n",
       "      <td>1</td>\n",
       "      <td>50</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  test  hw3\n",
       "0   Amy  sophmore    88    9\n",
       "1  Mike  freshman    79    7\n",
       "2  Jake    junior    93    8\n",
       "3  Rose  freshman    99    9\n",
       "4   Dan  freshman     1   50"
      ]
     },
     "execution_count": 462,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#delete column; creates new df without deleted columns\n",
    "grades_df.drop(['hw1','hw2'],axis=1)\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 463,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
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       "\n",
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       "<table border=\"1\" class=\"dataframe\">\n",
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       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "      <th>hw3</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>Dan</td>\n",
       "      <td>freshman</td>\n",
       "      <td>3</td>\n",
       "      <td>5</td>\n",
       "      <td>1</td>\n",
       "      <td>50</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test  hw3\n",
       "0   Amy  sophmore   10    8    88    9\n",
       "3  Rose  freshman   10   10    99    9\n",
       "4   Dan  freshman    3    5     1   50"
      ]
     },
     "execution_count": 463,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#delete rows\n",
    "grades_lessRows=grades_df.drop([1,2],axis=0)\n",
    "grades_lessRows"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 464,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "      <th>hw3</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Dan</td>\n",
       "      <td>freshman</td>\n",
       "      <td>3</td>\n",
       "      <td>5</td>\n",
       "      <td>1</td>\n",
       "      <td>50</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test  hw3\n",
       "0   Amy  sophmore   10    8    88    9\n",
       "1  Rose  freshman   10   10    99    9\n",
       "2   Dan  freshman    3    5     1   50"
      ]
     },
     "execution_count": 464,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_lessRows.index=[0,1,2]\n",
    "grades_lessRows"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Sorting dataframes"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 465,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
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       "\n",
       "    .dataframe tbody tr th {\n",
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       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "      <th>hw3</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "      <td>7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "      <td>8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>Dan</td>\n",
       "      <td>freshman</td>\n",
       "      <td>3</td>\n",
       "      <td>5</td>\n",
       "      <td>1</td>\n",
       "      <td>50</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test  hw3\n",
       "0   Amy  sophmore   10    8    88    9\n",
       "1  Mike  freshman    4    6    79    7\n",
       "2  Jake    junior    9    9    93    8\n",
       "3  Rose  freshman   10   10    99    9\n",
       "4   Dan  freshman    3    5     1   50"
      ]
     },
     "execution_count": 465,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 466,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>hw3</th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>test</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>9</td>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>88</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>7</td>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>79</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>8</td>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>93</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>9</td>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>99</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>3</td>\n",
       "      <td>5</td>\n",
       "      <td>50</td>\n",
       "      <td>Dan</td>\n",
       "      <td>freshman</td>\n",
       "      <td>1</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   hw1  hw2  hw3  name    status  test\n",
       "0   10    8    9   Amy  sophmore    88\n",
       "1    4    6    7  Mike  freshman    79\n",
       "2    9    9    8  Jake    junior    93\n",
       "3   10   10    9  Rose  freshman    99\n",
       "4    3    5   50   Dan  freshman     1"
      ]
     },
     "execution_count": 466,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df.sort_index(axis=1)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 467,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "      <th>hw3</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>Dan</td>\n",
       "      <td>freshman</td>\n",
       "      <td>3</td>\n",
       "      <td>5</td>\n",
       "      <td>1</td>\n",
       "      <td>50</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "      <td>8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "      <td>7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test  hw3\n",
       "0   Amy  sophmore   10    8    88    9\n",
       "4   Dan  freshman    3    5     1   50\n",
       "2  Jake    junior    9    9    93    8\n",
       "1  Mike  freshman    4    6    79    7\n",
       "3  Rose  freshman   10   10    99    9"
      ]
     },
     "execution_count": 467,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df.sort_values(by='name')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 468,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>name</th>\n",
       "      <th>status</th>\n",
       "      <th>hw1</th>\n",
       "      <th>hw2</th>\n",
       "      <th>test</th>\n",
       "      <th>hw3</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>Dan</td>\n",
       "      <td>freshman</td>\n",
       "      <td>3</td>\n",
       "      <td>5</td>\n",
       "      <td>1</td>\n",
       "      <td>50</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mike</td>\n",
       "      <td>freshman</td>\n",
       "      <td>4</td>\n",
       "      <td>6</td>\n",
       "      <td>79</td>\n",
       "      <td>7</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Rose</td>\n",
       "      <td>freshman</td>\n",
       "      <td>10</td>\n",
       "      <td>10</td>\n",
       "      <td>99</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Jake</td>\n",
       "      <td>junior</td>\n",
       "      <td>9</td>\n",
       "      <td>9</td>\n",
       "      <td>93</td>\n",
       "      <td>8</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Amy</td>\n",
       "      <td>sophmore</td>\n",
       "      <td>10</td>\n",
       "      <td>8</td>\n",
       "      <td>88</td>\n",
       "      <td>9</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   name    status  hw1  hw2  test  hw3\n",
       "4   Dan  freshman    3    5     1   50\n",
       "1  Mike  freshman    4    6    79    7\n",
       "3  Rose  freshman   10   10    99    9\n",
       "2  Jake    junior    9    9    93    8\n",
       "0   Amy  sophmore   10    8    88    9"
      ]
     },
     "execution_count": 468,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "grades_df.sort_values(by=['status','name'])"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Practice with gapminder data  \n",
    "download data: https://github.com/AnnaWilliford/SWC_Fall2019_test/blob/master/gapminder.txt  \n",
    "Click on `RAW`, save link as    \n",
    "\n",
    "Read data in Python:  \n",
    "`data = pd.read_csv(\"gapminder.txt\", delimiter = \"\\t\")`  \n",
    "\n",
    "Answer these questions:\n",
    "\n",
    "\n",
    "1. Can you extract 3rd and 5th column of the dataset?\n",
    "2. Can you extract the list of countries in this dataset?  \n",
    "\n",
    "*Hint: use `unique` method\n",
    "3. Can you get a part of this dataset that includes information about Sweden?\n",
    "4. Can you extract all countries for which life expectancy is below 70 in the year 1957?\n",
    "5. Can you make a new column that contains population in units of millions of people?\n",
    "\n",
    "**Challenge 3.1** Answers\n",
    "\n",
    "1. data.iloc[:,[2,4]]\n",
    "2. data.country.unique()\n",
    "3. data[data.country == \"Sweden\" ]\n",
    "4. data.loc[(data.lifeExp<70) & (data.year==1957)]\n",
    "5. data['popM']=data['pop']/(10**6)\n",
    "\n",
    "\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 469,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
       "    }\n",
       "\n",
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       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>country</th>\n",
       "      <th>continent</th>\n",
       "      <th>year</th>\n",
       "      <th>lifeExp</th>\n",
       "      <th>pop</th>\n",
       "      <th>gdpPercap</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Afghanistan</td>\n",
       "      <td>Asia</td>\n",
       "      <td>1952</td>\n",
       "      <td>28.801</td>\n",
       "      <td>8425333</td>\n",
       "      <td>779.445314</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Afghanistan</td>\n",
       "      <td>Asia</td>\n",
       "      <td>1957</td>\n",
       "      <td>30.332</td>\n",
       "      <td>9240934</td>\n",
       "      <td>820.853030</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Afghanistan</td>\n",
       "      <td>Asia</td>\n",
       "      <td>1962</td>\n",
       "      <td>31.997</td>\n",
       "      <td>10267083</td>\n",
       "      <td>853.100710</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Afghanistan</td>\n",
       "      <td>Asia</td>\n",
       "      <td>1967</td>\n",
       "      <td>34.020</td>\n",
       "      <td>11537966</td>\n",
       "      <td>836.197138</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>Afghanistan</td>\n",
       "      <td>Asia</td>\n",
       "      <td>1972</td>\n",
       "      <td>36.088</td>\n",
       "      <td>13079460</td>\n",
       "      <td>739.981106</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "       country continent  year  lifeExp       pop   gdpPercap\n",
       "0  Afghanistan      Asia  1952   28.801   8425333  779.445314\n",
       "1  Afghanistan      Asia  1957   30.332   9240934  820.853030\n",
       "2  Afghanistan      Asia  1962   31.997  10267083  853.100710\n",
       "3  Afghanistan      Asia  1967   34.020  11537966  836.197138\n",
       "4  Afghanistan      Asia  1972   36.088  13079460  739.981106"
      ]
     },
     "execution_count": 469,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "data = pd.read_csv(\"gapminder.txt\", delimiter = \"\\t\")\n",
    "data.head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 470,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
       "        vertical-align: middle;\n",
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       "\n",
       "    .dataframe tbody tr th {\n",
       "        vertical-align: top;\n",
       "    }\n",
       "\n",
       "    .dataframe thead th {\n",
       "        text-align: right;\n",
       "    }\n",
       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>country</th>\n",
       "      <th>continent</th>\n",
       "      <th>year</th>\n",
       "      <th>lifeExp</th>\n",
       "      <th>pop</th>\n",
       "      <th>gdpPercap</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1699</th>\n",
       "      <td>Zimbabwe</td>\n",
       "      <td>Africa</td>\n",
       "      <td>1987</td>\n",
       "      <td>62.351</td>\n",
       "      <td>9216418</td>\n",
       "      <td>706.157306</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1700</th>\n",
       "      <td>Zimbabwe</td>\n",
       "      <td>Africa</td>\n",
       "      <td>1992</td>\n",
       "      <td>60.377</td>\n",
       "      <td>10704340</td>\n",
       "      <td>693.420786</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1701</th>\n",
       "      <td>Zimbabwe</td>\n",
       "      <td>Africa</td>\n",
       "      <td>1997</td>\n",
       "      <td>46.809</td>\n",
       "      <td>11404948</td>\n",
       "      <td>792.449960</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1702</th>\n",
       "      <td>Zimbabwe</td>\n",
       "      <td>Africa</td>\n",
       "      <td>2002</td>\n",
       "      <td>39.989</td>\n",
       "      <td>11926563</td>\n",
       "      <td>672.038623</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1703</th>\n",
       "      <td>Zimbabwe</td>\n",
       "      <td>Africa</td>\n",
       "      <td>2007</td>\n",
       "      <td>43.487</td>\n",
       "      <td>12311143</td>\n",
       "      <td>469.709298</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "       country continent  year  lifeExp       pop   gdpPercap\n",
       "1699  Zimbabwe    Africa  1987   62.351   9216418  706.157306\n",
       "1700  Zimbabwe    Africa  1992   60.377  10704340  693.420786\n",
       "1701  Zimbabwe    Africa  1997   46.809  11404948  792.449960\n",
       "1702  Zimbabwe    Africa  2002   39.989  11926563  672.038623\n",
       "1703  Zimbabwe    Africa  2007   43.487  12311143  469.709298"
      ]
     },
     "execution_count": 470,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "data.tail()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 471,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(1704, 6)"
      ]
     },
     "execution_count": 471,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "data.shape"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 472,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\n",
       "<style scoped>\n",
       "    .dataframe tbody tr th:only-of-type {\n",
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       "</style>\n",
       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>year</th>\n",
       "      <th>pop</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>1952</td>\n",
       "      <td>8425333</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>1957</td>\n",
       "      <td>9240934</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>1962</td>\n",
       "      <td>10267083</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>1967</td>\n",
       "      <td>11537966</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>1972</td>\n",
       "      <td>13079460</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "   year       pop\n",
       "0  1952   8425333\n",
       "1  1957   9240934\n",
       "2  1962  10267083\n",
       "3  1967  11537966\n",
       "4  1972  13079460"
      ]
     },
     "execution_count": 472,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#Can you extract 3rd and 5th column of the dataset?\n",
    "data.iloc[:,[2,4]].head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 473,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "array(['Afghanistan', 'Albania', 'Algeria', 'Angola', 'Argentina',\n",
       "       'Australia', 'Austria', 'Bahrain', 'Bangladesh', 'Belgium',\n",
       "       'Benin', 'Bolivia', 'Bosnia_and_Herzegovina', 'Botswana', 'Brazil',\n",
       "       'Bulgaria', 'Burkina_Faso', 'Burundi', 'Cambodia', 'Cameroon',\n",
       "       'Canada', 'Central_African_Republic', 'Chad', 'Chile', 'China',\n",
       "       'Colombia', 'Comoros', 'Congo_Dem_Rep', 'Congo_Rep', 'Costa_Rica',\n",
       "       \"Cote_d'Ivoire\", 'Croatia', 'Cuba', 'Czech_Republic', 'Denmark',\n",
       "       'Djibouti', 'Dominican_Republic', 'Ecuador', 'Egypt',\n",
       "       'El_Salvador', 'Equatorial_Guinea', 'Eritrea', 'Ethiopia',\n",
       "       'Finland', 'France', 'Gabon', 'Gambia', 'Germany', 'Ghana',\n",
       "       'Greece', 'Guatemala', 'Guinea', 'Guinea-Bissau', 'Haiti',\n",
       "       'Honduras', 'Hong_Kong_China', 'Hungary', 'Iceland', 'India',\n",
       "       'Indonesia', 'Iran', 'Iraq', 'Ireland', 'Israel', 'Italy',\n",
       "       'Jamaica', 'Japan', 'Jordan', 'Kenya', 'Korea_Dem_Rep',\n",
       "       'Korea_Rep', 'Kuwait', 'Lebanon', 'Lesotho', 'Liberia', 'Libya',\n",
       "       'Madagascar', 'Malawi', 'Malaysia', 'Mali', 'Mauritania',\n",
       "       'Mauritius', 'Mexico', 'Mongolia', 'Montenegro', 'Morocco',\n",
       "       'Mozambique', 'Myanmar', 'Namibia', 'Nepal', 'Netherlands',\n",
       "       'New_Zealand', 'Nicaragua', 'Niger', 'Nigeria', 'Norway', 'Oman',\n",
       "       'Pakistan', 'Panama', 'Paraguay', 'Peru', 'Philippines', 'Poland',\n",
       "       'Portugal', 'Puerto_Rico', 'Reunion', 'Romania', 'Rwanda',\n",
       "       'Sao_Tome_and_Principe', 'Saudi_Arabia', 'Senegal', 'Serbia',\n",
       "       'Sierra_Leone', 'Singapore', 'Slovak_Republic', 'Slovenia',\n",
       "       'Somalia', 'South_Africa', 'Spain', 'Sri_Lanka', 'Sudan',\n",
       "       'Swaziland', 'Sweden', 'Switzerland', 'Syria', 'Taiwan',\n",
       "       'Tanzania', 'Thailand', 'Togo', 'Trinidad_and_Tobago', 'Tunisia',\n",
       "       'Turkey', 'Uganda', 'United_Kingdom', 'United_States', 'Uruguay',\n",
       "       'Venezuela', 'Vietnam', 'West_Bank_and_Gaza', 'Yemen_Rep',\n",
       "       'Zambia', 'Zimbabwe'], dtype=object)"
      ]
     },
     "execution_count": 473,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#Can you extract the list of countries in this dataset?\n",
    "data['country'].unique()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 474,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
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       "<table border=\"1\" class=\"dataframe\">\n",
       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>country</th>\n",
       "      <th>continent</th>\n",
       "      <th>year</th>\n",
       "      <th>lifeExp</th>\n",
       "      <th>pop</th>\n",
       "      <th>gdpPercap</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1464</th>\n",
       "      <td>Sweden</td>\n",
       "      <td>Europe</td>\n",
       "      <td>1952</td>\n",
       "      <td>71.860</td>\n",
       "      <td>7124673</td>\n",
       "      <td>8527.844662</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1465</th>\n",
       "      <td>Sweden</td>\n",
       "      <td>Europe</td>\n",
       "      <td>1957</td>\n",
       "      <td>72.490</td>\n",
       "      <td>7363802</td>\n",
       "      <td>9911.878226</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1466</th>\n",
       "      <td>Sweden</td>\n",
       "      <td>Europe</td>\n",
       "      <td>1962</td>\n",
       "      <td>73.370</td>\n",
       "      <td>7561588</td>\n",
       "      <td>12329.441920</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1467</th>\n",
       "      <td>Sweden</td>\n",
       "      <td>Europe</td>\n",
       "      <td>1967</td>\n",
       "      <td>74.160</td>\n",
       "      <td>7867931</td>\n",
       "      <td>15258.296970</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1468</th>\n",
       "      <td>Sweden</td>\n",
       "      <td>Europe</td>\n",
       "      <td>1972</td>\n",
       "      <td>74.720</td>\n",
       "      <td>8122293</td>\n",
       "      <td>17832.024640</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1469</th>\n",
       "      <td>Sweden</td>\n",
       "      <td>Europe</td>\n",
       "      <td>1977</td>\n",
       "      <td>75.440</td>\n",
       "      <td>8251648</td>\n",
       "      <td>18855.725210</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1470</th>\n",
       "      <td>Sweden</td>\n",
       "      <td>Europe</td>\n",
       "      <td>1982</td>\n",
       "      <td>76.420</td>\n",
       "      <td>8325260</td>\n",
       "      <td>20667.381250</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1471</th>\n",
       "      <td>Sweden</td>\n",
       "      <td>Europe</td>\n",
       "      <td>1987</td>\n",
       "      <td>77.190</td>\n",
       "      <td>8421403</td>\n",
       "      <td>23586.929270</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1472</th>\n",
       "      <td>Sweden</td>\n",
       "      <td>Europe</td>\n",
       "      <td>1992</td>\n",
       "      <td>78.160</td>\n",
       "      <td>8718867</td>\n",
       "      <td>23880.016830</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1473</th>\n",
       "      <td>Sweden</td>\n",
       "      <td>Europe</td>\n",
       "      <td>1997</td>\n",
       "      <td>79.390</td>\n",
       "      <td>8897619</td>\n",
       "      <td>25266.594990</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1474</th>\n",
       "      <td>Sweden</td>\n",
       "      <td>Europe</td>\n",
       "      <td>2002</td>\n",
       "      <td>80.040</td>\n",
       "      <td>8954175</td>\n",
       "      <td>29341.630930</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1475</th>\n",
       "      <td>Sweden</td>\n",
       "      <td>Europe</td>\n",
       "      <td>2007</td>\n",
       "      <td>80.884</td>\n",
       "      <td>9031088</td>\n",
       "      <td>33859.748350</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "     country continent  year  lifeExp      pop     gdpPercap\n",
       "1464  Sweden    Europe  1952   71.860  7124673   8527.844662\n",
       "1465  Sweden    Europe  1957   72.490  7363802   9911.878226\n",
       "1466  Sweden    Europe  1962   73.370  7561588  12329.441920\n",
       "1467  Sweden    Europe  1967   74.160  7867931  15258.296970\n",
       "1468  Sweden    Europe  1972   74.720  8122293  17832.024640\n",
       "1469  Sweden    Europe  1977   75.440  8251648  18855.725210\n",
       "1470  Sweden    Europe  1982   76.420  8325260  20667.381250\n",
       "1471  Sweden    Europe  1987   77.190  8421403  23586.929270\n",
       "1472  Sweden    Europe  1992   78.160  8718867  23880.016830\n",
       "1473  Sweden    Europe  1997   79.390  8897619  25266.594990\n",
       "1474  Sweden    Europe  2002   80.040  8954175  29341.630930\n",
       "1475  Sweden    Europe  2007   80.884  9031088  33859.748350"
      ]
     },
     "execution_count": 474,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#Can you get a part of this dataset that includes information about Sweden?\n",
    "data.loc[data.country=='Sweden']"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 475,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
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       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>country</th>\n",
       "      <th>continent</th>\n",
       "      <th>year</th>\n",
       "      <th>lifeExp</th>\n",
       "      <th>pop</th>\n",
       "      <th>gdpPercap</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Afghanistan</td>\n",
       "      <td>Asia</td>\n",
       "      <td>1957</td>\n",
       "      <td>30.332</td>\n",
       "      <td>9240934</td>\n",
       "      <td>820.853030</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>13</th>\n",
       "      <td>Albania</td>\n",
       "      <td>Europe</td>\n",
       "      <td>1957</td>\n",
       "      <td>59.280</td>\n",
       "      <td>1476505</td>\n",
       "      <td>1942.284244</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>25</th>\n",
       "      <td>Algeria</td>\n",
       "      <td>Africa</td>\n",
       "      <td>1957</td>\n",
       "      <td>45.685</td>\n",
       "      <td>10270856</td>\n",
       "      <td>3013.976023</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>37</th>\n",
       "      <td>Angola</td>\n",
       "      <td>Africa</td>\n",
       "      <td>1957</td>\n",
       "      <td>31.999</td>\n",
       "      <td>4561361</td>\n",
       "      <td>3827.940465</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>49</th>\n",
       "      <td>Argentina</td>\n",
       "      <td>Americas</td>\n",
       "      <td>1957</td>\n",
       "      <td>64.399</td>\n",
       "      <td>19610538</td>\n",
       "      <td>6856.856212</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "        country continent  year  lifeExp       pop    gdpPercap\n",
       "1   Afghanistan      Asia  1957   30.332   9240934   820.853030\n",
       "13      Albania    Europe  1957   59.280   1476505  1942.284244\n",
       "25      Algeria    Africa  1957   45.685  10270856  3013.976023\n",
       "37       Angola    Africa  1957   31.999   4561361  3827.940465\n",
       "49    Argentina  Americas  1957   64.399  19610538  6856.856212"
      ]
     },
     "execution_count": 475,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "#Can you extract all countries for which life expectancy is below 70 in the year 1957?\n",
    "data.loc[(data.lifeExp<70) & (data.year==1957)].head()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 476,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "       country continent  year  lifeExp       pop   gdpPercap       popM\n",
      "0  Afghanistan      Asia  1952   28.801   8425333  779.445314   8.425333\n",
      "1  Afghanistan      Asia  1957   30.332   9240934  820.853030   9.240934\n",
      "2  Afghanistan      Asia  1962   31.997  10267083  853.100710  10.267083\n",
      "3  Afghanistan      Asia  1967   34.020  11537966  836.197138  11.537966\n",
      "4  Afghanistan      Asia  1972   36.088  13079460  739.981106  13.079460\n"
     ]
    }
   ],
   "source": [
    "#Can you make a new column that contains population in units of millions of people?\n",
    "data['popM']=data['pop']/(10**6)\n",
    "print(data.head())"
   ]
  }
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