json_parse_file.ipynb

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   "cells": [
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "# Parse JSON File\n",
      "\n",
      "This snippit was written by [Chris R. Albon](http://www.chrisralbon.com/) and is part of his collection of [well-documented Python snippits](/~https://github.com/chrisalbon/code_py). All code is written in Python 3 in iPython notebook and offered under the [Creative Commons Attribution-ShareAlike 4.0 International License](http://creativecommons.org/licenses/by-sa/4.0/\"><img alt=\"Creative Commons License)."
     ]
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "## Preliminaries"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "import json\n",
      "import pandas as pd\n",
      "import requests"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 31
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "## Get data"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Pull down some simple json data\n",
      "r = requests.get('http://api.zippopotam.us/us/ma/belmont')\n",
      "\n",
      "# Convert it into a python object\n",
      "data = r.json()"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 78
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# View the data\n",
      "data"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 79,
       "text": [
        "{'state abbreviation': 'MA',\n",
        " 'place name': 'Belmont',\n",
        " 'country abbreviation': 'US',\n",
        " 'state': 'Massachusetts',\n",
        " 'places': [{'longitude': '-71.4594',\n",
        "   'latitude': '42.4464',\n",
        "   'place name': 'Belmont',\n",
        "   'post code': '02178'},\n",
        "  {'longitude': '-71.2044',\n",
        "   'latitude': '42.4128',\n",
        "   'place name': 'Belmont',\n",
        "   'post code': '02478'}],\n",
        " 'country': 'United States'}"
       ]
      }
     ],
     "prompt_number": 79
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "## Parse data"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# One level deep\n",
      "data['places']"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 80,
       "text": [
        "[{'longitude': '-71.4594',\n",
        "  'latitude': '42.4464',\n",
        "  'place name': 'Belmont',\n",
        "  'post code': '02178'},\n",
        " {'longitude': '-71.2044',\n",
        "  'latitude': '42.4128',\n",
        "  'place name': 'Belmont',\n",
        "  'post code': '02478'}]"
       ]
      }
     ],
     "prompt_number": 80
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# One level deep, second element\n",
      "data['places'][1]"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 81,
       "text": [
        "{'longitude': '-71.2044',\n",
        " 'latitude': '42.4128',\n",
        " 'place name': 'Belmont',\n",
        " 'post code': '02478'}"
       ]
      }
     ],
     "prompt_number": 81
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# One level down, then second item, then it's longitude object\n",
      "data['places'][1]['longitude']"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "metadata": {},
       "output_type": "pyout",
       "prompt_number": 82,
       "text": [
        "'-71.2044'"
       ]
      }
     ],
     "prompt_number": 82
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "## Create a for loop to extract all lat/long coordinates"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# For each element, i, in data.places,\n",
      "for i in data['places']:\n",
      "    # print the latitude element and the longitude element\n",
      "    print(i['latitude'], i['longitude'])"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "42.4464 -71.4594\n",
        "42.4128 -71.2044\n"
       ]
      }
     ],
     "prompt_number": 130
    },
    {
     "cell_type": "markdown",
     "metadata": {},
     "source": [
      "## Same as above, but as a function"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Create a function that\n",
      "def extract_latlong(json):\n",
      "    # For each element, i, in data.places,\n",
      "    for i in data['places']:\n",
      "        # print the latitude element and the longitude element\n",
      "        print(i['latitude'], i['longitude'])"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [],
     "prompt_number": 139
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "# Run the function\n",
      "extract_latlong(data)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "42.4464 -71.4594\n",
        "42.4128 -71.2044\n"
       ]
      }
     ],
     "prompt_number": 144
    }
   ],
   "metadata": {}
  }
 ]
}