Group By

groupby.ipynb

{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import pandas as pd"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 82,
   "metadata": {},
   "outputs": [],
   "source": [
    "sales = {'weekday' : ['Sun', 'Mon', 'Mon', 'Sun', 'Tue', 'Sun', 'Tue'],\n",
    "         'bread' : [120, 234, 100, 260, 421, 223, 322],\n",
    "         'butter' : [20, 24, 90, 60, 53, 89, 76]\n",
    "}\n",
    "df = pd.DataFrame(sales)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 83,
   "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>weekday</th>\n",
       "      <th>bread</th>\n",
       "      <th>butter</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>Sun</td>\n",
       "      <td>120</td>\n",
       "      <td>20</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>Mon</td>\n",
       "      <td>234</td>\n",
       "      <td>24</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>Mon</td>\n",
       "      <td>100</td>\n",
       "      <td>90</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>Sun</td>\n",
       "      <td>260</td>\n",
       "      <td>60</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>Tue</td>\n",
       "      <td>421</td>\n",
       "      <td>53</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5</th>\n",
       "      <td>Sun</td>\n",
       "      <td>223</td>\n",
       "      <td>89</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>6</th>\n",
       "      <td>Tue</td>\n",
       "      <td>322</td>\n",
       "      <td>76</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "  weekday  bread  butter\n",
       "0     Sun    120      20\n",
       "1     Mon    234      24\n",
       "2     Mon    100      90\n",
       "3     Sun    260      60\n",
       "4     Tue    421      53\n",
       "5     Sun    223      89\n",
       "6     Tue    322      76"
      ]
     },
     "execution_count": 83,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 84,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "{'Mon': Int64Index([1, 2], dtype='int64'),\n",
       " 'Sun': Int64Index([0, 3, 5], dtype='int64'),\n",
       " 'Tue': Int64Index([4, 6], dtype='int64')}"
      ]
     },
     "execution_count": 84,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df_grouped = df.groupby(['weekday']) #Grouping by weekday\n",
    "df_grouped.groups"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 89,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "{'Not a Sunday': Int64Index([1, 2, 4, 6], dtype='int64'),\n",
       " 'Sunday': Int64Index([0, 3, 5], dtype='int64')}"
      ]
     },
     "execution_count": 89,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "condition = (df['weekday'] == 'Sun').map({True:'Sunday', False:'Not a Sunday'}) #Grouping by a condition\n",
    "df.groupby(condition).groups"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 85,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Mon\n",
      "  weekday  bread  butter\n",
      "1     Mon    234      24\n",
      "2     Mon    100      90\n",
      "\n",
      "\n",
      "Sun\n",
      "  weekday  bread  butter\n",
      "0     Sun    120      20\n",
      "3     Sun    260      60\n",
      "5     Sun    223      89\n",
      "\n",
      "\n",
      "Tue\n",
      "  weekday  bread  butter\n",
      "4     Tue    421      53\n",
      "6     Tue    322      76\n",
      "\n",
      "\n"
     ]
    }
   ],
   "source": [
    "for name,group in df_grouped:    #Interating through the groups\n",
    "    print(name)\n",
    "    print(group)\n",
    "    print('\\n')"
   ]
  }
 ],
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