def __total_deviation(self, activity_id):
stream_df = load_stream(self.database_driver, activity_id, 'latlng')
if stream_df is not None:
stream_df = lat_long_to_x_y(stream_df)
stream_df = smooth(stream_df, smooth_colname='x')
stream_df = smooth(stream_df, smooth_colname='y')
stream_df = derivative(stream_df, derivative_colname='x_smooth')
stream_df = derivative(stream_df, derivative_colname='y_smooth')
stream_df = rolling_similarity(stream_df, cosine_similarity, 'dx_smooth_dt', 'dy_smooth_dt')
try:
return np.nansum([cosine_to_deviation(cos)
for cos in stream_df.cosine_similarity_dx_smooth_dt_dy_smooth_dt])
except ValueError:
logging.warning('Failed to compute route deviation for activity %d, returning NaN' % activity_id)
return np.nan
else:
logging.warning('No gps stream available for activity %d, returning NaN' % activity_id)
return np.nan
def test_cosine_to_deviation(self):
"""Should return normalized angle between vectors, given a cosine similarity"""
self.assertAlmostEqual(cosine_to_deviation(1), 0, 9)
self.assertAlmostEqual(cosine_to_deviation(0), 0.5, 9)
self.assertAlmostEqual(cosine_to_deviation(-1), 1, 9)
self.assertAlmostEqual(cosine_to_deviation(0.5), 0.33333, 5)