Fix for extreme longitudes in Vincenty. #187
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In some weird edge cases (generated by Hypothesis), the while-loop in the Vincenty code never runs.
Below, difference between the two longitudes is very close to 2π, so the condition
`abs(lambda_lng - lambda_prime) > 10e-12` is not true.
```python
from geopy.distance import vincenty
vincenty((-80, -179.999999999999), (-80.0, 180.0))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File ".../geopy/distance.py", line 322, in __init__
super(vincenty, self).__init__(*args, **kwargs)
File ".../geopy/distance.py", line 115, in __init__
kilometers += self.measure(a, b)
File ".../geopy/distance.py", line 414, in measure
u_sq = cos_sq_alpha * (major ** 2 - minor ** 2) / minor ** 2
UnboundLocalError: local variable 'cos_sq_alpha' referenced before assignment
```
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I'm getting this error and would like for this to be merged. +1 |
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I too am getting this error. |
cffk
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May 6, 2017
Restore testing of distance with "make test". Merge karldw's pull request geopy#187 and modify test_should_recognize_equivalence_of_pos_and_neg_180_longitude to check this bug. This will address issue geopy#242 too. Change test_should_compute_destination_for_half_trip_around_equator so that it checks the path along the equator instead of over the pole and tighten up the accuracy of this test. Add test_miscellaneous_high_accuracy_cases for testing distance.geodesic.
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In some weird edge cases (generated by Hypothesis), the while-loop in the Vincenty code never runs.
Below, difference between the two longitudes is very close to 2π, so the condition
abs(lambda_lng - lambda_prime) > 10e-12is not true.