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# Inspired by http://code.activestate.com/recipes/285264-natural-string-sorting/

import re

digits = re.compile(r'(\d+|\D+)')
def natural_sort_key(item):
    if item is None or item == '':
        return None

    pieces = digits.findall(item)

signed0

from math import sqrt 

def cut(coords, distance):
    '''Splits a cartesian linestring at a given distance
    Returns None for either part if the length is 0    
    '''

    if distance <= 0:
        return None, list(tuple(j) for j in coords)

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''''
From http://code.activestate.com/recipes/363602-lazy-property-evaluation/

Usage:

class MyClass():
    @lazyloaded
    def config(self):
        return {'yay': 'nay'}

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def pairs(iterable):
    '''Generate pairs of items in iterable'''
    
    i = iter(iterable)
    prev = i.next()    
    for j in i:
        yield prev, j
        prev = j

signed0

from math import sin, cos, sqrt, asin, radians

RADIUS_EARTH_M = 6371200.0 #The Earth's mean radius in meters

def geographic_length(coords):
    '''Returns the length of a linestring in meters'''
    
    coords = ((radians(x), radians(y)) for x, y in coords)
    rad_dist = sum(_haversine_distance(*c) for c in pairs(coords))
    

signed0

'''From http://www.daniweb.com/software-development/python/code/216610
Modified to use logging instead of print statments

Usage:
@log_time
def my_function():
    pass
'''

import logging