def test_extract_point(grid, lat, lon):
import json
from cyclerouter.rk import Client
calc = grid.extract_point(lat, lon)
# make a request to the Google Elevation API
client = Client()
_, content = client.request(
'http://maps.googleapis.com/maps/api/elevation/json',
data=dict(locations='{},{}'.format(lat, lon),
sensor='false'))
content = json.loads(content)
assert content['status'] == 'OK'
assert 'results' in content
assert len(content['results']) == 1
result = content['results'][0]
desr = result['elevation']
res = result['resolution']
# assert the calculated value is within the resolution of Google's value
assert_allclose(calc, desr, atol=res / 2)
def test_against_google(grid):
import json
from cyclerouter.rk import Client
client = Client()
# make a request to the Google Elevation API
_, content = client.request(
'http://maps.googleapis.com/maps/api/elevation/json',
data=dict(path='{},{}|{},{}'.format(grid.lats[0], grid.lons[0],
grid.lats[-1], grid.lons[0]),
samples=100,
sensor='false'))
content = json.loads(content)
assert content['status'] == 'OK'
assert 'results' in content
data = np.empty(shape=(len(content['results']), 3))
for i, rec in enumerate(content['results']):
data[i] = [rec['location']['lat'],
rec['location']['lng'],
rec['elevation']]
data = data.view(type=np.recarray,
dtype=[('lats', float),
('lons', float),
('elev', float)])
fig, ax1 = plt.subplots(1, 1)
ax1.set_title("SRTM v Google (Lon = {})".format(grid.lons[0]))
ax1.set_xlabel("Latitude")
ax1.plot(grid.lats, grid[:, 0])
ax1.plot(data.lats, data.elev, 'r')
ax1.set_xlim(-38.5, -33.5)
ax1.set_ylim(-20, 200)
plt.show()