def postcodes_to_points(csv_file):
postcodes_not_listed = []
postcodes = {}
reader = csv.reader(csv_file)
for row in reader:
try:
lat, lng = grid_to_ll(float(row[2]), float(row[3]))
except:
warn("Postcode %s not given a location, using a nearby value" % row[0])
yield [row[0], Point(lat, lng)]
def OSGB36GridRefToETRS89(mapRef):
if len(mapRef) < 4:
raise ValueError("Map ref too short")
if len(mapRef) % 2 == 1:
six.print_(ValueError("Unexpected input length"))
coordLen = int((len(mapRef) - 2) / 2)
code = mapRef[:2]
east = int(mapRef[2:2 + coordLen]) * pow(10, 5 - coordLen)
nrth = int(mapRef[2 + coordLen:]) * pow(10, 5 - coordLen)
x1, y1 = parse_grid(code, east, nrth)
(x, y, h) = OSGB36_to_ETRS89(x1, y1)
(gla, glo) = grid_to_ll(x, y)
return (gla, glo)
def OSGB36GridRefToETRS89(mapRef):
if len(mapRef) < 4:
raise ValueError("Map ref too short")
if len(mapRef) % 2 == 1:
six.print_(ValueError("Unexpected input length"))
coordLen = int((len(mapRef) - 2) / 2)
code = mapRef[:2]
east = int(mapRef[2:2+coordLen])*pow(10,5-coordLen)
nrth = int(mapRef[2+coordLen:])*pow(10,5-coordLen)
x1, y1 = parse_grid(code, east, nrth)
(x,y,h) = OSGB36_to_ETRS89 (x1, y1)
(gla, glo) = grid_to_ll(x, y)
return (gla, glo)
def _transform_points(points):
return [grid_to_ll(*point) for point in points]
def test_grid_to_ll():
x = 614199.522
y = 159979.837
(gla, glo) = grid_to_ll(x, y)
assert_almost_equal(gla, 51.297880, places=6)
assert_almost_equal(glo, 1.072628, places=6)
