/usr/lib/python3/dist-packages/geopy/geohash.py is in python3-geopy 0.95.1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 | from geopy import Point
class Geohash(object):
ENCODE_MAP = '0123456789bcdefghjkmnpqrstuvwxyz'
DECODE_MAP = dict([(char, i) for i, char in enumerate(ENCODE_MAP)])
def __init__(self, point_class=Point, precision=12):
self.point_class = point_class
self.precision = precision
def encode(self, *args, **kwargs):
precision = kwargs.pop('precision', self.precision)
point = Point(*args, **kwargs)
lat_min, latitude, lat_max = -90, 0, 90
long_min, longitude, long_max = -180, 0, 180
string = ''
bytes = []
odd_bit = False
for i in range(precision):
byte = 0
for bit in (16, 8, 4, 2, 1):
if odd_bit:
if point.latitude >= latitude:
byte |= bit
lat_min = latitude
else:
lat_max = latitude
latitude = (lat_min + lat_max) / 2.
else:
if point.longitude >= longitude:
byte |= bit
long_min = longitude
else:
long_max = longitude
longitude = (long_min + long_max) / 2.
odd_bit = not odd_bit
bytes.append(byte)
return ''.join([self.ENCODE_MAP[byte] for byte in bytes])
def decode(self, string):
lat_min, latitude, lat_max = -90, 0, 90
long_min, longitude, long_max = -180, 0, 180
odd_bit = False
for char in string:
try:
byte = self.DECODE_MAP[char]
except KeyError:
raise ValueError("Invalid hash: unexpected character %r." % (char,))
else:
for bit in (16, 8, 4, 2, 1):
if odd_bit:
if byte & bit:
lat_min = latitude
else:
lat_max = latitude
latitude = (lat_min + lat_max) / 2.
else:
if byte & bit:
long_min = longitude
else:
long_max = longitude
longitude = (long_min + long_max) / 2.
odd_bit = not odd_bit
point = self.point_class((latitude, longitude))
point.error = (lat_max - latitude, long_max - longitude)
return point
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