ch_02/4-inspecting_dataframes.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Inspecting a DataFrame Object\n",
    "\n",
    "## About the Data\n",
    "In this notebook, we will be working with earthquake data from September 18, 2018 - October 13, 2018 (obtained from the US Geological Survey (USGS) using the [USGS API](https://earthquake.usgs.gov/fdsnws/event/1/))\n",
    "\n",
    "## Setup\n",
    "We will be working with the `data/earthquakes.csv` file again, so we need to handle our imports and read it in."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "import numpy as np\n",
    "import pandas as pd\n",
    "\n",
    "df = pd.read_csv('data/earthquakes.csv')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Examining dataframes\n",
    "### Is it empty?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "False"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.empty"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### What are the dimensions?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "(9332, 26)"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.shape"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### What columns do we have?\n",
    "We know there are 26 columns, but what are they? Let's use the `columns` attribute to see:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "Index(['alert', 'cdi', 'code', 'detail', 'dmin', 'felt', 'gap', 'ids', 'mag',\n",
       "       'magType', 'mmi', 'net', 'nst', 'place', 'rms', 'sig', 'sources',\n",
       "       'status', 'time', 'title', 'tsunami', 'type', 'types', 'tz', 'updated',\n",
       "       'url'],\n",
       "      dtype='object')"
      ]
     },
     "execution_count": 4,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.columns"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### What does the data look like?\n",
    "View rows from the top with `head()`:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "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>alert</th>\n",
       "      <th>cdi</th>\n",
       "      <th>code</th>\n",
       "      <th>detail</th>\n",
       "      <th>dmin</th>\n",
       "      <th>felt</th>\n",
       "      <th>gap</th>\n",
       "      <th>ids</th>\n",
       "      <th>mag</th>\n",
       "      <th>magType</th>\n",
       "      <th>...</th>\n",
       "      <th>sources</th>\n",
       "      <th>status</th>\n",
       "      <th>time</th>\n",
       "      <th>title</th>\n",
       "      <th>tsunami</th>\n",
       "      <th>type</th>\n",
       "      <th>types</th>\n",
       "      <th>tz</th>\n",
       "      <th>updated</th>\n",
       "      <th>url</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>0</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>37389218</td>\n",
       "      <td>https://earthquake.usgs.gov/fdsnws/event/1/que...</td>\n",
       "      <td>0.008693</td>\n",
       "      <td>NaN</td>\n",
       "      <td>85.0</td>\n",
       "      <td>,ci37389218,</td>\n",
       "      <td>1.35</td>\n",
       "      <td>ml</td>\n",
       "      <td>...</td>\n",
       "      <td>,ci,</td>\n",
       "      <td>automatic</td>\n",
       "      <td>1539475168010</td>\n",
       "      <td>M 1.4 - 9km NE of Aguanga, CA</td>\n",
       "      <td>0</td>\n",
       "      <td>earthquake</td>\n",
       "      <td>,geoserve,nearby-cities,origin,phase-data,</td>\n",
       "      <td>-480.0</td>\n",
       "      <td>1539475395144</td>\n",
       "      <td>https://earthquake.usgs.gov/earthquakes/eventp...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>1</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>37389202</td>\n",
       "      <td>https://earthquake.usgs.gov/fdsnws/event/1/que...</td>\n",
       "      <td>0.020030</td>\n",
       "      <td>NaN</td>\n",
       "      <td>79.0</td>\n",
       "      <td>,ci37389202,</td>\n",
       "      <td>1.29</td>\n",
       "      <td>ml</td>\n",
       "      <td>...</td>\n",
       "      <td>,ci,</td>\n",
       "      <td>automatic</td>\n",
       "      <td>1539475129610</td>\n",
       "      <td>M 1.3 - 9km NE of Aguanga, CA</td>\n",
       "      <td>0</td>\n",
       "      <td>earthquake</td>\n",
       "      <td>,geoserve,nearby-cities,origin,phase-data,</td>\n",
       "      <td>-480.0</td>\n",
       "      <td>1539475253925</td>\n",
       "      <td>https://earthquake.usgs.gov/earthquakes/eventp...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>2</th>\n",
       "      <td>NaN</td>\n",
       "      <td>4.4</td>\n",
       "      <td>37389194</td>\n",
       "      <td>https://earthquake.usgs.gov/fdsnws/event/1/que...</td>\n",
       "      <td>0.021370</td>\n",
       "      <td>28.0</td>\n",
       "      <td>21.0</td>\n",
       "      <td>,ci37389194,</td>\n",
       "      <td>3.42</td>\n",
       "      <td>ml</td>\n",
       "      <td>...</td>\n",
       "      <td>,ci,</td>\n",
       "      <td>automatic</td>\n",
       "      <td>1539475062610</td>\n",
       "      <td>M 3.4 - 8km NE of Aguanga, CA</td>\n",
       "      <td>0</td>\n",
       "      <td>earthquake</td>\n",
       "      <td>,dyfi,focal-mechanism,geoserve,nearby-cities,o...</td>\n",
       "      <td>-480.0</td>\n",
       "      <td>1539536756176</td>\n",
       "      <td>https://earthquake.usgs.gov/earthquakes/eventp...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>3</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>37389186</td>\n",
       "      <td>https://earthquake.usgs.gov/fdsnws/event/1/que...</td>\n",
       "      <td>0.026180</td>\n",
       "      <td>NaN</td>\n",
       "      <td>39.0</td>\n",
       "      <td>,ci37389186,</td>\n",
       "      <td>0.44</td>\n",
       "      <td>ml</td>\n",
       "      <td>...</td>\n",
       "      <td>,ci,</td>\n",
       "      <td>automatic</td>\n",
       "      <td>1539474978070</td>\n",
       "      <td>M 0.4 - 9km NE of Aguanga, CA</td>\n",
       "      <td>0</td>\n",
       "      <td>earthquake</td>\n",
       "      <td>,geoserve,nearby-cities,origin,phase-data,</td>\n",
       "      <td>-480.0</td>\n",
       "      <td>1539475196167</td>\n",
       "      <td>https://earthquake.usgs.gov/earthquakes/eventp...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>4</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>73096941</td>\n",
       "      <td>https://earthquake.usgs.gov/fdsnws/event/1/que...</td>\n",
       "      <td>0.077990</td>\n",
       "      <td>NaN</td>\n",
       "      <td>192.0</td>\n",
       "      <td>,nc73096941,</td>\n",
       "      <td>2.16</td>\n",
       "      <td>md</td>\n",
       "      <td>...</td>\n",
       "      <td>,nc,</td>\n",
       "      <td>automatic</td>\n",
       "      <td>1539474716050</td>\n",
       "      <td>M 2.2 - 10km NW of Avenal, CA</td>\n",
       "      <td>0</td>\n",
       "      <td>earthquake</td>\n",
       "      <td>,geoserve,nearby-cities,origin,phase-data,scit...</td>\n",
       "      <td>-480.0</td>\n",
       "      <td>1539477547926</td>\n",
       "      <td>https://earthquake.usgs.gov/earthquakes/eventp...</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>5 rows × 26 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "  alert  cdi      code                                             detail  \\\n",
       "0   NaN  NaN  37389218  https://earthquake.usgs.gov/fdsnws/event/1/que...   \n",
       "1   NaN  NaN  37389202  https://earthquake.usgs.gov/fdsnws/event/1/que...   \n",
       "2   NaN  4.4  37389194  https://earthquake.usgs.gov/fdsnws/event/1/que...   \n",
       "3   NaN  NaN  37389186  https://earthquake.usgs.gov/fdsnws/event/1/que...   \n",
       "4   NaN  NaN  73096941  https://earthquake.usgs.gov/fdsnws/event/1/que...   \n",
       "\n",
       "       dmin  felt    gap           ids   mag magType  ...  sources     status  \\\n",
       "0  0.008693   NaN   85.0  ,ci37389218,  1.35      ml  ...     ,ci,  automatic   \n",
       "1  0.020030   NaN   79.0  ,ci37389202,  1.29      ml  ...     ,ci,  automatic   \n",
       "2  0.021370  28.0   21.0  ,ci37389194,  3.42      ml  ...     ,ci,  automatic   \n",
       "3  0.026180   NaN   39.0  ,ci37389186,  0.44      ml  ...     ,ci,  automatic   \n",
       "4  0.077990   NaN  192.0  ,nc73096941,  2.16      md  ...     ,nc,  automatic   \n",
       "\n",
       "            time                          title  tsunami        type  \\\n",
       "0  1539475168010  M 1.4 - 9km NE of Aguanga, CA        0  earthquake   \n",
       "1  1539475129610  M 1.3 - 9km NE of Aguanga, CA        0  earthquake   \n",
       "2  1539475062610  M 3.4 - 8km NE of Aguanga, CA        0  earthquake   \n",
       "3  1539474978070  M 0.4 - 9km NE of Aguanga, CA        0  earthquake   \n",
       "4  1539474716050  M 2.2 - 10km NW of Avenal, CA        0  earthquake   \n",
       "\n",
       "                                               types     tz        updated  \\\n",
       "0         ,geoserve,nearby-cities,origin,phase-data, -480.0  1539475395144   \n",
       "1         ,geoserve,nearby-cities,origin,phase-data, -480.0  1539475253925   \n",
       "2  ,dyfi,focal-mechanism,geoserve,nearby-cities,o... -480.0  1539536756176   \n",
       "3         ,geoserve,nearby-cities,origin,phase-data, -480.0  1539475196167   \n",
       "4  ,geoserve,nearby-cities,origin,phase-data,scit... -480.0  1539477547926   \n",
       "\n",
       "                                                 url  \n",
       "0  https://earthquake.usgs.gov/earthquakes/eventp...  \n",
       "1  https://earthquake.usgs.gov/earthquakes/eventp...  \n",
       "2  https://earthquake.usgs.gov/earthquakes/eventp...  \n",
       "3  https://earthquake.usgs.gov/earthquakes/eventp...  \n",
       "4  https://earthquake.usgs.gov/earthquakes/eventp...  \n",
       "\n",
       "[5 rows x 26 columns]"
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.head()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "View rows from the bottom with `tail()`. Let's view 2 rows:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "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>alert</th>\n",
       "      <th>cdi</th>\n",
       "      <th>code</th>\n",
       "      <th>detail</th>\n",
       "      <th>dmin</th>\n",
       "      <th>felt</th>\n",
       "      <th>gap</th>\n",
       "      <th>ids</th>\n",
       "      <th>mag</th>\n",
       "      <th>magType</th>\n",
       "      <th>...</th>\n",
       "      <th>sources</th>\n",
       "      <th>status</th>\n",
       "      <th>time</th>\n",
       "      <th>title</th>\n",
       "      <th>tsunami</th>\n",
       "      <th>type</th>\n",
       "      <th>types</th>\n",
       "      <th>tz</th>\n",
       "      <th>updated</th>\n",
       "      <th>url</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>9330</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>38063959</td>\n",
       "      <td>https://earthquake.usgs.gov/fdsnws/event/1/que...</td>\n",
       "      <td>0.01865</td>\n",
       "      <td>NaN</td>\n",
       "      <td>61.0</td>\n",
       "      <td>,ci38063959,</td>\n",
       "      <td>1.10</td>\n",
       "      <td>ml</td>\n",
       "      <td>...</td>\n",
       "      <td>,ci,</td>\n",
       "      <td>reviewed</td>\n",
       "      <td>1537229545350</td>\n",
       "      <td>M 1.1 - 9km NE of Aguanga, CA</td>\n",
       "      <td>0</td>\n",
       "      <td>earthquake</td>\n",
       "      <td>,focal-mechanism,geoserve,nearby-cities,origin...</td>\n",
       "      <td>-480.0</td>\n",
       "      <td>1537230211640</td>\n",
       "      <td>https://earthquake.usgs.gov/earthquakes/eventp...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>9331</th>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>38063935</td>\n",
       "      <td>https://earthquake.usgs.gov/fdsnws/event/1/que...</td>\n",
       "      <td>0.01698</td>\n",
       "      <td>NaN</td>\n",
       "      <td>39.0</td>\n",
       "      <td>,ci38063935,</td>\n",
       "      <td>0.66</td>\n",
       "      <td>ml</td>\n",
       "      <td>...</td>\n",
       "      <td>,ci,</td>\n",
       "      <td>reviewed</td>\n",
       "      <td>1537228864470</td>\n",
       "      <td>M 0.7 - 9km NE of Aguanga, CA</td>\n",
       "      <td>0</td>\n",
       "      <td>earthquake</td>\n",
       "      <td>,focal-mechanism,geoserve,nearby-cities,origin...</td>\n",
       "      <td>-480.0</td>\n",
       "      <td>1537305830770</td>\n",
       "      <td>https://earthquake.usgs.gov/earthquakes/eventp...</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>2 rows × 26 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "     alert  cdi      code                                             detail  \\\n",
       "9330   NaN  NaN  38063959  https://earthquake.usgs.gov/fdsnws/event/1/que...   \n",
       "9331   NaN  NaN  38063935  https://earthquake.usgs.gov/fdsnws/event/1/que...   \n",
       "\n",
       "         dmin  felt   gap           ids   mag magType  ...  sources    status  \\\n",
       "9330  0.01865   NaN  61.0  ,ci38063959,  1.10      ml  ...     ,ci,  reviewed   \n",
       "9331  0.01698   NaN  39.0  ,ci38063935,  0.66      ml  ...     ,ci,  reviewed   \n",
       "\n",
       "               time                          title  tsunami        type  \\\n",
       "9330  1537229545350  M 1.1 - 9km NE of Aguanga, CA        0  earthquake   \n",
       "9331  1537228864470  M 0.7 - 9km NE of Aguanga, CA        0  earthquake   \n",
       "\n",
       "                                                  types     tz        updated  \\\n",
       "9330  ,focal-mechanism,geoserve,nearby-cities,origin... -480.0  1537230211640   \n",
       "9331  ,focal-mechanism,geoserve,nearby-cities,origin... -480.0  1537305830770   \n",
       "\n",
       "                                                    url  \n",
       "9330  https://earthquake.usgs.gov/earthquakes/eventp...  \n",
       "9331  https://earthquake.usgs.gov/earthquakes/eventp...  \n",
       "\n",
       "[2 rows x 26 columns]"
      ]
     },
     "execution_count": 6,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.tail(2)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "*Tip: we can modify the display options in order to see more columns:*\n",
    "\n",
    "```python\n",
    "# check the max columns setting\n",
    ">>> pd.get_option('display.max_columns')\n",
    "20\n",
    "\n",
    "# set the max columns to show when printing the dataframe to 26\n",
    ">>> pd.set_option('display.max_columns', 26)\n",
    "# OR\n",
    ">>> pd.options.display.max_columns = 26\n",
    "\n",
    "# reset the option\n",
    ">>> pd.reset_option('display.max_columns')\n",
    "\n",
    "# get information on all display settings\n",
    ">>> pd.describe_option('display')\n",
    "```\n",
    "\n",
    "*More information can be found in the documentation [here](https://pandas.pydata.org/pandas-docs/stable/user_guide/options.html).*\n",
    "\n",
    "### What data types do we have?"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "alert       object\n",
       "cdi        float64\n",
       "code        object\n",
       "detail      object\n",
       "dmin       float64\n",
       "felt       float64\n",
       "gap        float64\n",
       "ids         object\n",
       "mag        float64\n",
       "magType     object\n",
       "mmi        float64\n",
       "net         object\n",
       "nst        float64\n",
       "place       object\n",
       "rms        float64\n",
       "sig          int64\n",
       "sources     object\n",
       "status      object\n",
       "time         int64\n",
       "title       object\n",
       "tsunami      int64\n",
       "type        object\n",
       "types       object\n",
       "tz         float64\n",
       "updated      int64\n",
       "url         object\n",
       "dtype: object"
      ]
     },
     "execution_count": 7,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.dtypes"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Getting extra info and finding nulls"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "<class 'pandas.core.frame.DataFrame'>\n",
      "RangeIndex: 9332 entries, 0 to 9331\n",
      "Data columns (total 26 columns):\n",
      " #   Column   Non-Null Count  Dtype  \n",
      "---  ------   --------------  -----  \n",
      " 0   alert    59 non-null     object \n",
      " 1   cdi      329 non-null    float64\n",
      " 2   code     9332 non-null   object \n",
      " 3   detail   9332 non-null   object \n",
      " 4   dmin     6139 non-null   float64\n",
      " 5   felt     329 non-null    float64\n",
      " 6   gap      6164 non-null   float64\n",
      " 7   ids      9332 non-null   object \n",
      " 8   mag      9331 non-null   float64\n",
      " 9   magType  9331 non-null   object \n",
      " 10  mmi      93 non-null     float64\n",
      " 11  net      9332 non-null   object \n",
      " 12  nst      5364 non-null   float64\n",
      " 13  place    9332 non-null   object \n",
      " 14  rms      9332 non-null   float64\n",
      " 15  sig      9332 non-null   int64  \n",
      " 16  sources  9332 non-null   object \n",
      " 17  status   9332 non-null   object \n",
      " 18  time     9332 non-null   int64  \n",
      " 19  title    9332 non-null   object \n",
      " 20  tsunami  9332 non-null   int64  \n",
      " 21  type     9332 non-null   object \n",
      " 22  types    9332 non-null   object \n",
      " 23  tz       9331 non-null   float64\n",
      " 24  updated  9332 non-null   int64  \n",
      " 25  url      9332 non-null   object \n",
      "dtypes: float64(9), int64(4), object(13)\n",
      "memory usage: 1.9+ MB\n"
     ]
    }
   ],
   "source": [
    "df.info()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Describing and Summarizing\n",
    "### Get summary statistics"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "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>cdi</th>\n",
       "      <th>dmin</th>\n",
       "      <th>felt</th>\n",
       "      <th>gap</th>\n",
       "      <th>mag</th>\n",
       "      <th>mmi</th>\n",
       "      <th>nst</th>\n",
       "      <th>rms</th>\n",
       "      <th>sig</th>\n",
       "      <th>time</th>\n",
       "      <th>tsunami</th>\n",
       "      <th>tz</th>\n",
       "      <th>updated</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>count</th>\n",
       "      <td>329.000000</td>\n",
       "      <td>6139.000000</td>\n",
       "      <td>329.000000</td>\n",
       "      <td>6164.000000</td>\n",
       "      <td>9331.000000</td>\n",
       "      <td>93.000000</td>\n",
       "      <td>5364.000000</td>\n",
       "      <td>9332.000000</td>\n",
       "      <td>9332.000000</td>\n",
       "      <td>9.332000e+03</td>\n",
       "      <td>9332.000000</td>\n",
       "      <td>9331.000000</td>\n",
       "      <td>9.332000e+03</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>mean</th>\n",
       "      <td>2.754711</td>\n",
       "      <td>0.544925</td>\n",
       "      <td>12.310030</td>\n",
       "      <td>121.506588</td>\n",
       "      <td>1.497345</td>\n",
       "      <td>3.651398</td>\n",
       "      <td>19.053878</td>\n",
       "      <td>0.362122</td>\n",
       "      <td>56.899914</td>\n",
       "      <td>1.538284e+12</td>\n",
       "      <td>0.006537</td>\n",
       "      <td>-451.990140</td>\n",
       "      <td>1.538537e+12</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>std</th>\n",
       "      <td>1.010637</td>\n",
       "      <td>2.214305</td>\n",
       "      <td>48.954944</td>\n",
       "      <td>72.962363</td>\n",
       "      <td>1.203347</td>\n",
       "      <td>1.790523</td>\n",
       "      <td>15.492315</td>\n",
       "      <td>0.317784</td>\n",
       "      <td>91.872163</td>\n",
       "      <td>6.080306e+08</td>\n",
       "      <td>0.080589</td>\n",
       "      <td>231.752571</td>\n",
       "      <td>6.564135e+08</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>min</th>\n",
       "      <td>0.000000</td>\n",
       "      <td>0.000648</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>12.000000</td>\n",
       "      <td>-1.260000</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>1.537229e+12</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>-720.000000</td>\n",
       "      <td>1.537230e+12</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>25%</th>\n",
       "      <td>2.000000</td>\n",
       "      <td>0.020425</td>\n",
       "      <td>1.000000</td>\n",
       "      <td>66.142500</td>\n",
       "      <td>0.720000</td>\n",
       "      <td>2.680000</td>\n",
       "      <td>8.000000</td>\n",
       "      <td>0.119675</td>\n",
       "      <td>8.000000</td>\n",
       "      <td>1.537793e+12</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>-540.000000</td>\n",
       "      <td>1.537996e+12</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>50%</th>\n",
       "      <td>2.700000</td>\n",
       "      <td>0.059050</td>\n",
       "      <td>2.000000</td>\n",
       "      <td>105.000000</td>\n",
       "      <td>1.300000</td>\n",
       "      <td>3.720000</td>\n",
       "      <td>15.000000</td>\n",
       "      <td>0.210000</td>\n",
       "      <td>26.000000</td>\n",
       "      <td>1.538245e+12</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>-480.000000</td>\n",
       "      <td>1.538621e+12</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>75%</th>\n",
       "      <td>3.300000</td>\n",
       "      <td>0.177250</td>\n",
       "      <td>5.000000</td>\n",
       "      <td>159.000000</td>\n",
       "      <td>1.900000</td>\n",
       "      <td>4.570000</td>\n",
       "      <td>25.000000</td>\n",
       "      <td>0.590000</td>\n",
       "      <td>56.000000</td>\n",
       "      <td>1.538766e+12</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>-480.000000</td>\n",
       "      <td>1.539110e+12</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>max</th>\n",
       "      <td>8.400000</td>\n",
       "      <td>53.737000</td>\n",
       "      <td>580.000000</td>\n",
       "      <td>355.910000</td>\n",
       "      <td>7.500000</td>\n",
       "      <td>9.120000</td>\n",
       "      <td>172.000000</td>\n",
       "      <td>1.910000</td>\n",
       "      <td>2015.000000</td>\n",
       "      <td>1.539475e+12</td>\n",
       "      <td>1.000000</td>\n",
       "      <td>720.000000</td>\n",
       "      <td>1.539537e+12</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "              cdi         dmin        felt          gap          mag  \\\n",
       "count  329.000000  6139.000000  329.000000  6164.000000  9331.000000   \n",
       "mean     2.754711     0.544925   12.310030   121.506588     1.497345   \n",
       "std      1.010637     2.214305   48.954944    72.962363     1.203347   \n",
       "min      0.000000     0.000648    0.000000    12.000000    -1.260000   \n",
       "25%      2.000000     0.020425    1.000000    66.142500     0.720000   \n",
       "50%      2.700000     0.059050    2.000000   105.000000     1.300000   \n",
       "75%      3.300000     0.177250    5.000000   159.000000     1.900000   \n",
       "max      8.400000    53.737000  580.000000   355.910000     7.500000   \n",
       "\n",
       "             mmi          nst          rms          sig          time  \\\n",
       "count  93.000000  5364.000000  9332.000000  9332.000000  9.332000e+03   \n",
       "mean    3.651398    19.053878     0.362122    56.899914  1.538284e+12   \n",
       "std     1.790523    15.492315     0.317784    91.872163  6.080306e+08   \n",
       "min     0.000000     0.000000     0.000000     0.000000  1.537229e+12   \n",
       "25%     2.680000     8.000000     0.119675     8.000000  1.537793e+12   \n",
       "50%     3.720000    15.000000     0.210000    26.000000  1.538245e+12   \n",
       "75%     4.570000    25.000000     0.590000    56.000000  1.538766e+12   \n",
       "max     9.120000   172.000000     1.910000  2015.000000  1.539475e+12   \n",
       "\n",
       "           tsunami           tz       updated  \n",
       "count  9332.000000  9331.000000  9.332000e+03  \n",
       "mean      0.006537  -451.990140  1.538537e+12  \n",
       "std       0.080589   231.752571  6.564135e+08  \n",
       "min       0.000000  -720.000000  1.537230e+12  \n",
       "25%       0.000000  -540.000000  1.537996e+12  \n",
       "50%       0.000000  -480.000000  1.538621e+12  \n",
       "75%       0.000000  -480.000000  1.539110e+12  \n",
       "max       1.000000   720.000000  1.539537e+12  "
      ]
     },
     "execution_count": 9,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.describe()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Specifying the 5<sup>th</sup> and 95<sup>th</sup> percentile:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
       "<div>\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>cdi</th>\n",
       "      <th>dmin</th>\n",
       "      <th>felt</th>\n",
       "      <th>gap</th>\n",
       "      <th>mag</th>\n",
       "      <th>mmi</th>\n",
       "      <th>nst</th>\n",
       "      <th>rms</th>\n",
       "      <th>sig</th>\n",
       "      <th>time</th>\n",
       "      <th>tsunami</th>\n",
       "      <th>tz</th>\n",
       "      <th>updated</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>count</th>\n",
       "      <td>329.000000</td>\n",
       "      <td>6139.000000</td>\n",
       "      <td>329.000000</td>\n",
       "      <td>6164.000000</td>\n",
       "      <td>9331.000000</td>\n",
       "      <td>93.000000</td>\n",
       "      <td>5364.000000</td>\n",
       "      <td>9332.000000</td>\n",
       "      <td>9332.000000</td>\n",
       "      <td>9.332000e+03</td>\n",
       "      <td>9332.000000</td>\n",
       "      <td>9331.000000</td>\n",
       "      <td>9.332000e+03</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>mean</th>\n",
       "      <td>2.754711</td>\n",
       "      <td>0.544925</td>\n",
       "      <td>12.310030</td>\n",
       "      <td>121.506588</td>\n",
       "      <td>1.497345</td>\n",
       "      <td>3.651398</td>\n",
       "      <td>19.053878</td>\n",
       "      <td>0.362122</td>\n",
       "      <td>56.899914</td>\n",
       "      <td>1.538284e+12</td>\n",
       "      <td>0.006537</td>\n",
       "      <td>-451.990140</td>\n",
       "      <td>1.538537e+12</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>std</th>\n",
       "      <td>1.010637</td>\n",
       "      <td>2.214305</td>\n",
       "      <td>48.954944</td>\n",
       "      <td>72.962363</td>\n",
       "      <td>1.203347</td>\n",
       "      <td>1.790523</td>\n",
       "      <td>15.492315</td>\n",
       "      <td>0.317784</td>\n",
       "      <td>91.872163</td>\n",
       "      <td>6.080306e+08</td>\n",
       "      <td>0.080589</td>\n",
       "      <td>231.752571</td>\n",
       "      <td>6.564135e+08</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>min</th>\n",
       "      <td>0.000000</td>\n",
       "      <td>0.000648</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>12.000000</td>\n",
       "      <td>-1.260000</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>1.537229e+12</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>-720.000000</td>\n",
       "      <td>1.537230e+12</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>5%</th>\n",
       "      <td>2.000000</td>\n",
       "      <td>0.005491</td>\n",
       "      <td>1.000000</td>\n",
       "      <td>35.000000</td>\n",
       "      <td>-0.040000</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>4.000000</td>\n",
       "      <td>0.030000</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>1.537344e+12</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>-600.000000</td>\n",
       "      <td>1.537387e+12</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>50%</th>\n",
       "      <td>2.700000</td>\n",
       "      <td>0.059050</td>\n",
       "      <td>2.000000</td>\n",
       "      <td>105.000000</td>\n",
       "      <td>1.300000</td>\n",
       "      <td>3.720000</td>\n",
       "      <td>15.000000</td>\n",
       "      <td>0.210000</td>\n",
       "      <td>26.000000</td>\n",
       "      <td>1.538245e+12</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>-480.000000</td>\n",
       "      <td>1.538621e+12</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>95%</th>\n",
       "      <td>4.300000</td>\n",
       "      <td>2.678900</td>\n",
       "      <td>40.200000</td>\n",
       "      <td>276.000000</td>\n",
       "      <td>4.400000</td>\n",
       "      <td>6.380000</td>\n",
       "      <td>49.000000</td>\n",
       "      <td>0.960000</td>\n",
       "      <td>298.000000</td>\n",
       "      <td>1.539319e+12</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>-60.000000</td>\n",
       "      <td>1.539400e+12</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>max</th>\n",
       "      <td>8.400000</td>\n",
       "      <td>53.737000</td>\n",
       "      <td>580.000000</td>\n",
       "      <td>355.910000</td>\n",
       "      <td>7.500000</td>\n",
       "      <td>9.120000</td>\n",
       "      <td>172.000000</td>\n",
       "      <td>1.910000</td>\n",
       "      <td>2015.000000</td>\n",
       "      <td>1.539475e+12</td>\n",
       "      <td>1.000000</td>\n",
       "      <td>720.000000</td>\n",
       "      <td>1.539537e+12</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "              cdi         dmin        felt          gap          mag  \\\n",
       "count  329.000000  6139.000000  329.000000  6164.000000  9331.000000   \n",
       "mean     2.754711     0.544925   12.310030   121.506588     1.497345   \n",
       "std      1.010637     2.214305   48.954944    72.962363     1.203347   \n",
       "min      0.000000     0.000648    0.000000    12.000000    -1.260000   \n",
       "5%       2.000000     0.005491    1.000000    35.000000    -0.040000   \n",
       "50%      2.700000     0.059050    2.000000   105.000000     1.300000   \n",
       "95%      4.300000     2.678900   40.200000   276.000000     4.400000   \n",
       "max      8.400000    53.737000  580.000000   355.910000     7.500000   \n",
       "\n",
       "             mmi          nst          rms          sig          time  \\\n",
       "count  93.000000  5364.000000  9332.000000  9332.000000  9.332000e+03   \n",
       "mean    3.651398    19.053878     0.362122    56.899914  1.538284e+12   \n",
       "std     1.790523    15.492315     0.317784    91.872163  6.080306e+08   \n",
       "min     0.000000     0.000000     0.000000     0.000000  1.537229e+12   \n",
       "5%      0.000000     4.000000     0.030000     0.000000  1.537344e+12   \n",
       "50%     3.720000    15.000000     0.210000    26.000000  1.538245e+12   \n",
       "95%     6.380000    49.000000     0.960000   298.000000  1.539319e+12   \n",
       "max     9.120000   172.000000     1.910000  2015.000000  1.539475e+12   \n",
       "\n",
       "           tsunami           tz       updated  \n",
       "count  9332.000000  9331.000000  9.332000e+03  \n",
       "mean      0.006537  -451.990140  1.538537e+12  \n",
       "std       0.080589   231.752571  6.564135e+08  \n",
       "min       0.000000  -720.000000  1.537230e+12  \n",
       "5%        0.000000  -600.000000  1.537387e+12  \n",
       "50%       0.000000  -480.000000  1.538621e+12  \n",
       "95%       0.000000   -60.000000  1.539400e+12  \n",
       "max       1.000000   720.000000  1.539537e+12  "
      ]
     },
     "execution_count": 10,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.describe(percentiles=[0.05, 0.95])"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Describe specific data types:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/html": [
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       "  <thead>\n",
       "    <tr style=\"text-align: right;\">\n",
       "      <th></th>\n",
       "      <th>alert</th>\n",
       "      <th>code</th>\n",
       "      <th>detail</th>\n",
       "      <th>ids</th>\n",
       "      <th>magType</th>\n",
       "      <th>net</th>\n",
       "      <th>place</th>\n",
       "      <th>sources</th>\n",
       "      <th>status</th>\n",
       "      <th>title</th>\n",
       "      <th>type</th>\n",
       "      <th>types</th>\n",
       "      <th>url</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>count</th>\n",
       "      <td>59</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>9331</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>unique</th>\n",
       "      <td>2</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>10</td>\n",
       "      <td>14</td>\n",
       "      <td>5433</td>\n",
       "      <td>52</td>\n",
       "      <td>2</td>\n",
       "      <td>7807</td>\n",
       "      <td>5</td>\n",
       "      <td>42</td>\n",
       "      <td>9332</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>top</th>\n",
       "      <td>green</td>\n",
       "      <td>20262789</td>\n",
       "      <td>https://earthquake.usgs.gov/fdsnws/event/1/que...</td>\n",
       "      <td>,pr2018277012,</td>\n",
       "      <td>ml</td>\n",
       "      <td>ak</td>\n",
       "      <td>10km NE of Aguanga, CA</td>\n",
       "      <td>,ak,</td>\n",
       "      <td>reviewed</td>\n",
       "      <td>M 0.4 - 10km NE of Aguanga, CA</td>\n",
       "      <td>earthquake</td>\n",
       "      <td>,geoserve,origin,phase-data,</td>\n",
       "      <td>https://earthquake.usgs.gov/earthquakes/eventp...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>freq</th>\n",
       "      <td>58</td>\n",
       "      <td>1</td>\n",
       "      <td>1</td>\n",
       "      <td>1</td>\n",
       "      <td>6803</td>\n",
       "      <td>3166</td>\n",
       "      <td>306</td>\n",
       "      <td>2981</td>\n",
       "      <td>7797</td>\n",
       "      <td>55</td>\n",
       "      <td>9081</td>\n",
       "      <td>5301</td>\n",
       "      <td>1</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "</div>"
      ],
      "text/plain": [
       "        alert      code                                             detail  \\\n",
       "count      59      9332                                               9332   \n",
       "unique      2      9332                                               9332   \n",
       "top     green  20262789  https://earthquake.usgs.gov/fdsnws/event/1/que...   \n",
       "freq       58         1                                                  1   \n",
       "\n",
       "                   ids magType   net                   place sources  \\\n",
       "count             9332    9331  9332                    9332    9332   \n",
       "unique            9332      10    14                    5433      52   \n",
       "top     ,pr2018277012,      ml    ak  10km NE of Aguanga, CA    ,ak,   \n",
       "freq                 1    6803  3166                     306    2981   \n",
       "\n",
       "          status                           title        type  \\\n",
       "count       9332                            9332        9332   \n",
       "unique         2                            7807           5   \n",
       "top     reviewed  M 0.4 - 10km NE of Aguanga, CA  earthquake   \n",
       "freq        7797                              55        9081   \n",
       "\n",
       "                               types  \\\n",
       "count                           9332   \n",
       "unique                            42   \n",
       "top     ,geoserve,origin,phase-data,   \n",
       "freq                            5301   \n",
       "\n",
       "                                                      url  \n",
       "count                                                9332  \n",
       "unique                                               9332  \n",
       "top     https://earthquake.usgs.gov/earthquakes/eventp...  \n",
       "freq                                                    1  "
      ]
     },
     "execution_count": 11,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.describe(include=np.object)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Or describe all of them:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "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>alert</th>\n",
       "      <th>cdi</th>\n",
       "      <th>code</th>\n",
       "      <th>detail</th>\n",
       "      <th>dmin</th>\n",
       "      <th>felt</th>\n",
       "      <th>gap</th>\n",
       "      <th>ids</th>\n",
       "      <th>mag</th>\n",
       "      <th>magType</th>\n",
       "      <th>...</th>\n",
       "      <th>sources</th>\n",
       "      <th>status</th>\n",
       "      <th>time</th>\n",
       "      <th>title</th>\n",
       "      <th>tsunami</th>\n",
       "      <th>type</th>\n",
       "      <th>types</th>\n",
       "      <th>tz</th>\n",
       "      <th>updated</th>\n",
       "      <th>url</th>\n",
       "    </tr>\n",
       "  </thead>\n",
       "  <tbody>\n",
       "    <tr>\n",
       "      <th>count</th>\n",
       "      <td>59</td>\n",
       "      <td>329.000000</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>6139.000000</td>\n",
       "      <td>329.000000</td>\n",
       "      <td>6164.000000</td>\n",
       "      <td>9332</td>\n",
       "      <td>9331.000000</td>\n",
       "      <td>9331</td>\n",
       "      <td>...</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>9.332000e+03</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332.000000</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>9331.000000</td>\n",
       "      <td>9.332000e+03</td>\n",
       "      <td>9332</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>unique</th>\n",
       "      <td>2</td>\n",
       "      <td>NaN</td>\n",
       "      <td>9332</td>\n",
       "      <td>9332</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>9332</td>\n",
       "      <td>NaN</td>\n",
       "      <td>10</td>\n",
       "      <td>...</td>\n",
       "      <td>52</td>\n",
       "      <td>2</td>\n",
       "      <td>NaN</td>\n",
       "      <td>7807</td>\n",
       "      <td>NaN</td>\n",
       "      <td>5</td>\n",
       "      <td>42</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>9332</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>top</th>\n",
       "      <td>green</td>\n",
       "      <td>NaN</td>\n",
       "      <td>20262789</td>\n",
       "      <td>https://earthquake.usgs.gov/fdsnws/event/1/que...</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>,pr2018277012,</td>\n",
       "      <td>NaN</td>\n",
       "      <td>ml</td>\n",
       "      <td>...</td>\n",
       "      <td>,ak,</td>\n",
       "      <td>reviewed</td>\n",
       "      <td>NaN</td>\n",
       "      <td>M 0.4 - 10km NE of Aguanga, CA</td>\n",
       "      <td>NaN</td>\n",
       "      <td>earthquake</td>\n",
       "      <td>,geoserve,origin,phase-data,</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>https://earthquake.usgs.gov/earthquakes/eventp...</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>freq</th>\n",
       "      <td>58</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1</td>\n",
       "      <td>1</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1</td>\n",
       "      <td>NaN</td>\n",
       "      <td>6803</td>\n",
       "      <td>...</td>\n",
       "      <td>2981</td>\n",
       "      <td>7797</td>\n",
       "      <td>NaN</td>\n",
       "      <td>55</td>\n",
       "      <td>NaN</td>\n",
       "      <td>9081</td>\n",
       "      <td>5301</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>mean</th>\n",
       "      <td>NaN</td>\n",
       "      <td>2.754711</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>0.544925</td>\n",
       "      <td>12.310030</td>\n",
       "      <td>121.506588</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1.497345</td>\n",
       "      <td>NaN</td>\n",
       "      <td>...</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1.538284e+12</td>\n",
       "      <td>NaN</td>\n",
       "      <td>0.006537</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>-451.990140</td>\n",
       "      <td>1.538537e+12</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>std</th>\n",
       "      <td>NaN</td>\n",
       "      <td>1.010637</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>2.214305</td>\n",
       "      <td>48.954944</td>\n",
       "      <td>72.962363</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1.203347</td>\n",
       "      <td>NaN</td>\n",
       "      <td>...</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>6.080306e+08</td>\n",
       "      <td>NaN</td>\n",
       "      <td>0.080589</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>231.752571</td>\n",
       "      <td>6.564135e+08</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>min</th>\n",
       "      <td>NaN</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>0.000648</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>12.000000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>-1.260000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>...</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1.537229e+12</td>\n",
       "      <td>NaN</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>-720.000000</td>\n",
       "      <td>1.537230e+12</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>25%</th>\n",
       "      <td>NaN</td>\n",
       "      <td>2.000000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>0.020425</td>\n",
       "      <td>1.000000</td>\n",
       "      <td>66.142500</td>\n",
       "      <td>NaN</td>\n",
       "      <td>0.720000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>...</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1.537793e+12</td>\n",
       "      <td>NaN</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>-540.000000</td>\n",
       "      <td>1.537996e+12</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>50%</th>\n",
       "      <td>NaN</td>\n",
       "      <td>2.700000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>0.059050</td>\n",
       "      <td>2.000000</td>\n",
       "      <td>105.000000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1.300000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>...</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1.538245e+12</td>\n",
       "      <td>NaN</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>-480.000000</td>\n",
       "      <td>1.538621e+12</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>75%</th>\n",
       "      <td>NaN</td>\n",
       "      <td>3.300000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>0.177250</td>\n",
       "      <td>5.000000</td>\n",
       "      <td>159.000000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1.900000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>...</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1.538766e+12</td>\n",
       "      <td>NaN</td>\n",
       "      <td>0.000000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>-480.000000</td>\n",
       "      <td>1.539110e+12</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "    <tr>\n",
       "      <th>max</th>\n",
       "      <td>NaN</td>\n",
       "      <td>8.400000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>53.737000</td>\n",
       "      <td>580.000000</td>\n",
       "      <td>355.910000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>7.500000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>...</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1.539475e+12</td>\n",
       "      <td>NaN</td>\n",
       "      <td>1.000000</td>\n",
       "      <td>NaN</td>\n",
       "      <td>NaN</td>\n",
       "      <td>720.000000</td>\n",
       "      <td>1.539537e+12</td>\n",
       "      <td>NaN</td>\n",
       "    </tr>\n",
       "  </tbody>\n",
       "</table>\n",
       "<p>11 rows × 26 columns</p>\n",
       "</div>"
      ],
      "text/plain": [
       "        alert         cdi      code  \\\n",
       "count      59  329.000000      9332   \n",
       "unique      2         NaN      9332   \n",
       "top     green         NaN  20262789   \n",
       "freq       58         NaN         1   \n",
       "mean      NaN    2.754711       NaN   \n",
       "std       NaN    1.010637       NaN   \n",
       "min       NaN    0.000000       NaN   \n",
       "25%       NaN    2.000000       NaN   \n",
       "50%       NaN    2.700000       NaN   \n",
       "75%       NaN    3.300000       NaN   \n",
       "max       NaN    8.400000       NaN   \n",
       "\n",
       "                                                   detail         dmin  \\\n",
       "count                                                9332  6139.000000   \n",
       "unique                                               9332          NaN   \n",
       "top     https://earthquake.usgs.gov/fdsnws/event/1/que...          NaN   \n",
       "freq                                                    1          NaN   \n",
       "mean                                                  NaN     0.544925   \n",
       "std                                                   NaN     2.214305   \n",
       "min                                                   NaN     0.000648   \n",
       "25%                                                   NaN     0.020425   \n",
       "50%                                                   NaN     0.059050   \n",
       "75%                                                   NaN     0.177250   \n",
       "max                                                   NaN    53.737000   \n",
       "\n",
       "              felt          gap             ids          mag magType  ...  \\\n",
       "count   329.000000  6164.000000            9332  9331.000000    9331  ...   \n",
       "unique         NaN          NaN            9332          NaN      10  ...   \n",
       "top            NaN          NaN  ,pr2018277012,          NaN      ml  ...   \n",
       "freq           NaN          NaN               1          NaN    6803  ...   \n",
       "mean     12.310030   121.506588             NaN     1.497345     NaN  ...   \n",
       "std      48.954944    72.962363             NaN     1.203347     NaN  ...   \n",
       "min       0.000000    12.000000             NaN    -1.260000     NaN  ...   \n",
       "25%       1.000000    66.142500             NaN     0.720000     NaN  ...   \n",
       "50%       2.000000   105.000000             NaN     1.300000     NaN  ...   \n",
       "75%       5.000000   159.000000             NaN     1.900000     NaN  ...   \n",
       "max     580.000000   355.910000             NaN     7.500000     NaN  ...   \n",
       "\n",
       "        sources    status          time                           title  \\\n",
       "count      9332      9332  9.332000e+03                            9332   \n",
       "unique       52         2           NaN                            7807   \n",
       "top        ,ak,  reviewed           NaN  M 0.4 - 10km NE of Aguanga, CA   \n",
       "freq       2981      7797           NaN                              55   \n",
       "mean        NaN       NaN  1.538284e+12                             NaN   \n",
       "std         NaN       NaN  6.080306e+08                             NaN   \n",
       "min         NaN       NaN  1.537229e+12                             NaN   \n",
       "25%         NaN       NaN  1.537793e+12                             NaN   \n",
       "50%         NaN       NaN  1.538245e+12                             NaN   \n",
       "75%         NaN       NaN  1.538766e+12                             NaN   \n",
       "max         NaN       NaN  1.539475e+12                             NaN   \n",
       "\n",
       "            tsunami        type                         types           tz  \\\n",
       "count   9332.000000        9332                          9332  9331.000000   \n",
       "unique          NaN           5                            42          NaN   \n",
       "top             NaN  earthquake  ,geoserve,origin,phase-data,          NaN   \n",
       "freq            NaN        9081                          5301          NaN   \n",
       "mean       0.006537         NaN                           NaN  -451.990140   \n",
       "std        0.080589         NaN                           NaN   231.752571   \n",
       "min        0.000000         NaN                           NaN  -720.000000   \n",
       "25%        0.000000         NaN                           NaN  -540.000000   \n",
       "50%        0.000000         NaN                           NaN  -480.000000   \n",
       "75%        0.000000         NaN                           NaN  -480.000000   \n",
       "max        1.000000         NaN                           NaN   720.000000   \n",
       "\n",
       "             updated                                                url  \n",
       "count   9.332000e+03                                               9332  \n",
       "unique           NaN                                               9332  \n",
       "top              NaN  https://earthquake.usgs.gov/earthquakes/eventp...  \n",
       "freq             NaN                                                  1  \n",
       "mean    1.538537e+12                                                NaN  \n",
       "std     6.564135e+08                                                NaN  \n",
       "min     1.537230e+12                                                NaN  \n",
       "25%     1.537996e+12                                                NaN  \n",
       "50%     1.538621e+12                                                NaN  \n",
       "75%     1.539110e+12                                                NaN  \n",
       "max     1.539537e+12                                                NaN  \n",
       "\n",
       "[11 rows x 26 columns]"
      ]
     },
     "execution_count": 12,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.describe(include='all')"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "This works on columns also:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "count    329.000000\n",
       "mean      12.310030\n",
       "std       48.954944\n",
       "min        0.000000\n",
       "25%        1.000000\n",
       "50%        2.000000\n",
       "75%        5.000000\n",
       "max      580.000000\n",
       "Name: felt, dtype: float64"
      ]
     },
     "execution_count": 13,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.felt.describe()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "There are methods for specific statistics as well. Here is a sampling of them:\n",
    "\n",
    "| Method | Description | Data types |\n",
    "| --- | --- | --- |\n",
    "| `count()` | The number of non-null observations | Any |\n",
    "| `nunique()` | The number of unique values | Any |\n",
    "| `sum()` | The total of the values | Numerical or Boolean |\n",
    "| `mean()` | The average of the values | Numerical or Boolean |\n",
    "| `median()` | The median of the values | Numerical |\n",
    "| `min()` | The minimum of the values | Numerical |\n",
    "| `idxmin()` | The index where the minimum values occurs | Numerical |\n",
    "| `max()` | The maximum of the values | Numerical |\n",
    "| `idxmax()` | The index where the maximum value occurs | Numerical |\n",
    "| `abs()` | The absolute values of the data | Numerical |\n",
    "| `std()` | The standard deviation | Numerical |\n",
    "| `var()` | The variance |  Numerical |\n",
    "| `cov()` | The covariance between two `Series`, or a covariance matrix for all column combinations in a `DataFrame` | Numerical |\n",
    "| `corr()` | The correlation between two `Series`, or a correlation matrix for all column combinations in a `DataFrame` | Numerical |\n",
    "| `quantile()` | Calculates a specific quantile | Numerical |\n",
    "| `cumsum()` | The cumulative sum | Numerical or Boolean |\n",
    "| `cummin()` | The cumulative minimum | Numerical |\n",
    "| `cummax()` | The cumulative maximum | Numerical |\n",
    "\n",
    "For example, finding the unique values in the `alert` column:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "array([nan, 'green', 'red'], dtype=object)"
      ]
     },
     "execution_count": 14,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.alert.unique()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "We can then use `value_counts()` to see how many of each unique value we have:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "green    58\n",
       "red       1\n",
       "Name: alert, dtype: int64"
      ]
     },
     "execution_count": 15,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "df.alert.value_counts()"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Note that `Index` objects also have several methods to help describe and summarize our data:\n",
    "\n",
    "| Method | Description |\n",
    "| --- | --- |\n",
    "| `argmax()`/`argmin()` | Find the location of the maximum/minimum value in the index |\n",
    "| `equals()` | Compare the index to another `Index` object for equality |\n",
    "| `isin()` | Check if the index values are in a list of values and return an array of Booleans |\n",
    "| `max()`/`min()` | Find the maximum/minimum value in the index |\n",
    "| `nunique()` | Get the number of unique values in the index |\n",
    "| `to_series()` | Create a `Series` object from the index |\n",
    "| `unique()` | Find the unique values of the index |\n",
    "| `value_counts()`| Create a frequency table for the unique values in the index |"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "<hr>\n",
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   ]
  }
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