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  {
   "cells": [
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "# Converting Strings To Datetime\n",
      "\n",
      "- **Author:** [Chris Albon](http://www.chrisalbon.com/), [@ChrisAlbon](https://twitter.com/chrisalbon)\n",
      "- **Date:** -\n",
      "- **Repo:** [Python 3 code snippets for data science](https://github.com/chrisalbon/code_py)\n",
      "- **Note:**"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "### Datetime formating"
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "** Type - Description** \n",
      "- %Y - 4-digit year\n",
      "- %y - 2-digit year\n",
      "- %m - 2-digit month [01, 12]\n",
      "- %d - 2-digit day [01, 31]\n",
      "- %H - Hour (24-hour clock) [00, 23]\n",
      "- %I - Hour (12-hour clock) [01, 12]\n",
      "- %M - 2-digit minute [00, 59]\n",
      "- %S - Second [00, 61] (seconds 60, 61 account for leap seconds) \n",
      "- %w - Weekday as integer [0 (Sunday), 6]\n",
      "- %U - Week number of the year [00, 53]. Sunday is considered the first day of the week, and days before the first Sunday of the year are \u201cweek 0\u201d.\n",
      "- %W - Week number of the year [00, 53]. Monday is considered the first day of the week, and days before the first Monday of the year are \u201cweek 0\u201d.\n",
      "- %z - UTC time zone offset as +HHMM or -HHMM, empty if time zone naive %F \n",
      "- %F - Shortcut for %Y-%m-%d, for example 2012-4-18\n",
      "- %D - Shortcut for %m/%d/%y, for example 04/18/12\n",
      "\n",
      "\n",
      "\n",
      "\n",
      "\n",
      "\n",
      "\n",
      "\n",
      "\n",
      "\n",
      "\n",
      "\n",
      " \n",
      " \n",
      " \n",
      " "
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "### Import modules"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "from datetime import datetime\n",
      "from dateutil.parser import parse\n",
      "import pandas as pd"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 24
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "### Create a string variable with the war start time"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "war_start = '2011-01-03'"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 25
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "### Convert the string to datetime format"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "datetime.strptime(war_start, '%Y-%m-%d')"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 26,
       "text": [
        "datetime.datetime(2011, 1, 3, 0, 0)"
       ]
      }
     ],
     "prompt_number": 26
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "### Create a list of strings as dates"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "attack_dates = ['7/2/2011', '8/6/2012', '11/13/2013', '5/26/2011', '5/2/2001']"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 27
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "### Convert attack_dates strings into datetime format"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "[datetime.strptime(x, '%m/%d/%Y') for x in attack_dates]"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 28,
       "text": [
        "[datetime.datetime(2011, 7, 2, 0, 0),\n",
        " datetime.datetime(2012, 8, 6, 0, 0),\n",
        " datetime.datetime(2013, 11, 13, 0, 0),\n",
        " datetime.datetime(2011, 5, 26, 0, 0),\n",
        " datetime.datetime(2001, 5, 2, 0, 0)]"
       ]
      }
     ],
     "prompt_number": 28
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "### Use parse() to attempt to auto-convert common string formats"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "parse(war_start)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 29,
       "text": [
        "datetime.datetime(2011, 1, 3, 0, 0)"
       ]
      }
     ],
     "prompt_number": 29
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "### Use parse() on every element of the attack_dates string"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "[parse(x) for x in attack_dates]"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 30,
       "text": [
        "[datetime.datetime(2011, 7, 2, 0, 0),\n",
        " datetime.datetime(2012, 8, 6, 0, 0),\n",
        " datetime.datetime(2013, 11, 13, 0, 0),\n",
        " datetime.datetime(2011, 5, 26, 0, 0),\n",
        " datetime.datetime(2001, 5, 2, 0, 0)]"
       ]
      }
     ],
     "prompt_number": 30
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "### Use parse, but designate that the day is first"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "parse(war_start, dayfirst=True)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 31,
       "text": [
        "datetime.datetime(2011, 1, 3, 0, 0)"
       ]
      }
     ],
     "prompt_number": 31
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "### Create a dataframe"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "data = {'date': ['2014-05-01 18:47:05.069722', '2014-05-01 18:47:05.119994', '2014-05-02 18:47:05.178768', '2014-05-02 18:47:05.230071', '2014-05-02 18:47:05.230071', '2014-05-02 18:47:05.280592', '2014-05-03 18:47:05.332662', '2014-05-03 18:47:05.385109', '2014-05-04 18:47:05.436523', '2014-05-04 18:47:05.486877'], \n",
      "        'value': [1, 1, 1, 1, 1, 1, 1, 1, 1, 1]}\n",
      "df = pd.DataFrame(data, columns = ['date', 'value'])\n",
      "print(df)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "                         date  value\n",
        "0  2014-05-01 18:47:05.069722      1\n",
        "1  2014-05-01 18:47:05.119994      1\n",
        "2  2014-05-02 18:47:05.178768      1\n",
        "3  2014-05-02 18:47:05.230071      1\n",
        "4  2014-05-02 18:47:05.230071      1\n",
        "5  2014-05-02 18:47:05.280592      1\n",
        "6  2014-05-03 18:47:05.332662      1\n",
        "7  2014-05-03 18:47:05.385109      1\n",
        "8  2014-05-04 18:47:05.436523      1\n",
        "9  2014-05-04 18:47:05.486877      1\n",
        "\n",
        "[10 rows x 2 columns]\n"
       ]
      }
     ],
     "prompt_number": 32
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "### Convert df['date'] from string to datetime"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "pd.to_datetime(df['date'])"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 37,
       "text": [
        "0   2014-05-01 18:47:05.069722\n",
        "1   2014-05-01 18:47:05.119994\n",
        "2   2014-05-02 18:47:05.178768\n",
        "3   2014-05-02 18:47:05.230071\n",
        "4   2014-05-02 18:47:05.230071\n",
        "5   2014-05-02 18:47:05.280592\n",
        "6   2014-05-03 18:47:05.332662\n",
        "7   2014-05-03 18:47:05.385109\n",
        "8   2014-05-04 18:47:05.436523\n",
        "9   2014-05-04 18:47:05.486877\n",
        "Name: date, dtype: datetime64[ns]"
       ]
      }
     ],
     "prompt_number": 37
    }
   ],
   "metadata": {}
  }
 ]
}