Demo showing that Python is effective at processing GeoJson data, as the format is similar to Python's dictionary object type.

extract_weekly_dates_from_geojson.py

#! usr/bin/env/python

# loop through input data and add one feature per week to output data
# create a while loop with a counter that adds 7 days from start day and
# maxes out at an end date

from sys import argv
import simplejson as json
from datetime import datetime, timedelta

script, infile, outfile = argv

data = json.load(open(infile, 'r'))
output = open(outfile, 'w')

geojson = {
	"type": "FeatureCollection",
	"features": []
	}

def push_data(input):
	"""
	adds features from input file incrementing by week
	"""
	
	for feature in input['features']:
		# if feature.geometry != null
		if feature['geometry'] != None:
		    
		    date = datetime.strptime(feature['properties']['date'], '%m/%d/%Y')

		    # print stuff to debug...
		    print "date: ", date
		    print "geometry x: ", feature['geometry']['coordinates'][0]
		    print "geometry y: ", feature['geometry']['coordinates'][1]
            
                    #create variables for while loop 
		    start_date = datetime.strptime('5/6/2013', '%m/%d/%Y')
		    end_date = datetime.strptime('9/20/2013', '%m/%d/%Y')
		    match_date = start_date

		    #create variables for input data to append to output data
		    mileage = feature['properties']['interval']
		    total_miles = feature['properties']['total']
		    x = feature['geometry']['coordinates'][0]
		    y = feature["geometry"]["coordinates"][1]

		    # loop over dates and add one feature per week to output
		    while  match_date < end_date:
				if date == match_date:
					geojson["features"].append(
						{
							"type": "Feature",
							"geometry": {
							    "type": "Point",
							    "coordinates": [x,y]
								},
							"properties": {
								"date": date.strftime('%m/%d/%Y'),
								"mileage": mileage,
								"total miles": total_miles
								}
						})

				# increase the match_date variable by one week
				match_date += timedelta(days=7)


push_data(data)
json.dump(geojson, output)