From a489bfa5f9c5b01d1b8c79d11e875d4265dd5f64 Mon Sep 17 00:00:00 2001
From: Raphael <raphael.sturgis@lis-lab.fr>
Date: Thu, 10 Feb 2022 11:26:15 +0100
Subject: [PATCH] Ais trajectory shifting
---
.gitignore | 3 +
skais/ais/ais_trajectory.py | 53 ++++++++++++++++++
skais/tests/ais/test_ais_trajectory.py | 40 ++++++++++++-
skais/tests/utils/test_geography.py | 39 +++++++++++++
.../utils/__pycache__/__init__.cpython-38.pyc | Bin 167 -> 0 bytes
.../__pycache__/geography.cpython-38.pyc | Bin 746 -> 0 bytes
skais/utils/geography.py | 20 ++++++-
7 files changed, 151 insertions(+), 4 deletions(-)
create mode 100644 skais/tests/utils/test_geography.py
delete mode 100644 skais/utils/__pycache__/__init__.cpython-38.pyc
delete mode 100644 skais/utils/__pycache__/geography.cpython-38.pyc
diff --git a/.gitignore b/.gitignore
index b139f3e..400aa52 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,6 @@ build/
skais.egg-info/
*.coverage
*__pycache__*
+venv/
+
+local.*
\ No newline at end of file
diff --git a/skais/ais/ais_trajectory.py b/skais/ais/ais_trajectory.py
index de9b6b0..5b2af98 100644
--- a/skais/ais/ais_trajectory.py
+++ b/skais/ais/ais_trajectory.py
@@ -1,8 +1,11 @@
+import random
+
import pandas as pd
import numpy as np
from numba import jit
from scipy.interpolate import interp1d
+from skais.utils.geography import great_circle, position_from_distance
from skais.ais.ais_points import AISPoints
@@ -154,3 +157,53 @@ class AISTrajectory(AISPoints):
index += i
return result
+
+ def shift_trajectory_to_coordinates(self, target_coordinate=(0, 0), point_index=None, in_place=False):
+ if point_index is None:
+ point_index = random.randint(0, len(self.df.index) - 1)
+
+ df = self.df.copy()
+ new_df = df.copy()
+
+ new_df['latitude'].iat[point_index] = target_coordinate[0]
+ new_df['longitude'].iat[point_index] = target_coordinate[1]
+
+ new_point = target_coordinate
+ for i in range(point_index, 0, -1):
+ current_point = (df.iloc[i]['latitude'], df.iloc[i]['longitude'])
+ lat_dist = great_circle(current_point[0], df.iloc[i - 1]['latitude'], current_point[1], current_point[1])
+ long_dist = great_circle(current_point[0], current_point[0], current_point[1], df.iloc[i - 1]['longitude'])
+
+ if current_point[0] > df.iloc[i - 1]['latitude']:
+ lat_dist *= -1
+
+ if current_point[1] > df.iloc[i - 1]['longitude']:
+ long_dist *= -1
+
+ new_point = position_from_distance(new_point, (lat_dist, long_dist))
+
+ new_df['latitude'].iat[i - 1] = new_point[0]
+ new_df['longitude'].iat[i - 1] = new_point[1]
+
+ new_point = target_coordinate
+ for i in range(point_index, len(df.index) - 1):
+ current_point = (df.iloc[i]['latitude'], df.iloc[i]['longitude'])
+ lat_dist = great_circle(current_point[0], df.iloc[i + 1]['latitude'], current_point[1], current_point[1])
+ long_dist = great_circle(current_point[0], current_point[0], current_point[1], df.iloc[i + 1]['longitude'])
+
+ if current_point[0] > df.iloc[i + 1]['latitude']:
+ lat_dist *= -1
+
+ if current_point[1] > df.iloc[i + 1]['longitude']:
+ long_dist *= -1
+
+ new_point = position_from_distance(new_point, (lat_dist, long_dist))
+
+ new_df['latitude'].iat[i + 1] = new_point[0]
+ new_df['longitude'].iat[i + 1] = new_point[1]
+
+ if in_place:
+ self.df = new_df
+ return self
+ else:
+ return AISTrajectory(new_df, mmsi=self.mmsi)
diff --git a/skais/tests/ais/test_ais_trajectory.py b/skais/tests/ais/test_ais_trajectory.py
index 799825c..8d46240 100644
--- a/skais/tests/ais/test_ais_trajectory.py
+++ b/skais/tests/ais/test_ais_trajectory.py
@@ -319,4 +319,42 @@ class TestAISTrajectory(unittest.TestCase):
self.assertEqual(0, compute_trajectory.py_func(times, 800))
def test_apply_func_on_window(self):
- self.assertRaises(ValueError, apply_func_on_window,np.arange(10), 0, 0, 'not valid string')
\ No newline at end of file
+ self.assertRaises(ValueError, apply_func_on_window,np.arange(10), 0, 0, 'not valid string')
+
+ def test_shift_trajectory_to_coordinates_no_change(self):
+ trajectory = AISTrajectory(
+ pd.DataFrame(
+ {
+ "latitude": [0, 90, 0, -90],
+ "longitude": [0, 90, 180, -90],
+ "ts_sec": [i for i in range(4)]
+ }
+ )
+ )
+
+ result = trajectory.shift_trajectory_to_coordinates(point_index=0)
+
+ pd.testing.assert_frame_equal(trajectory.df.reset_index(drop=True), result.df.reset_index(drop=True))
+
+ def test_shift_trajectory_to_coordinates_change_1(self):
+ trajectory = AISTrajectory(
+ pd.DataFrame(
+ {
+ "latitude": [1, 2, 3, 4],
+ "longitude": [1, 2, 3, 4],
+ "ts_sec": [i for i in range(4)]
+ }
+ )
+ )
+
+ result = trajectory.shift_trajectory_to_coordinates(point_index=0).df
+
+ expected = pd.DataFrame(
+ {
+ "latitude": [0, 2, 3, 4], # TBD
+ "longitude": [0, 1, 2, 3],
+ "ts_sec": [i for i in range(4)]
+ }
+ )
+
+ pd.testing.assert_frame_equal(expected.reset_index(drop=True), result.reset_index(drop=True))
\ No newline at end of file
diff --git a/skais/tests/utils/test_geography.py b/skais/tests/utils/test_geography.py
new file mode 100644
index 0000000..8316524
--- /dev/null
+++ b/skais/tests/utils/test_geography.py
@@ -0,0 +1,39 @@
+import unittest
+import numpy as np
+
+from skais.utils.geography import position_from_distance
+
+tol = 0.005
+
+
+class TestGeography(unittest.TestCase):
+ def test_position_from_distance_1(self):
+ position = (0, 0)
+ distance = (10000, 10000)
+
+ expected = (0.09, 0.09)
+ result = position_from_distance(position, distance)
+
+ np.testing.assert_allclose(expected, result, tol)
+
+ def test_position_from_distance_2(self):
+ position = (10, 10)
+ distance = (10000, 10000)
+
+ expected = (10.0636111, 10.064722222222223)
+ result = position_from_distance(position, distance)
+
+ np.testing.assert_allclose(expected, result, tol)
+
+ def test_position_from_distance_3(self):
+ position = (75, 75)
+ distance = (10000, -10000)
+
+ expected = (75.0633333, 74.75333333333333)
+ result = position_from_distance(position, distance)
+
+ np.testing.assert_allclose(expected, result, tol)
+
+
+if __name__ == '__main__':
+ unittest.main()
diff --git a/skais/utils/__pycache__/__init__.cpython-38.pyc b/skais/utils/__pycache__/__init__.cpython-38.pyc
deleted file mode 100644
index a9577174079f5508328c6cc2288ec7bc1d22e257..0000000000000000000000000000000000000000
GIT binary patch
literal 0
HcmV?d00001
literal 167
zcmWIL<>g{vU|_JY%SZsxk3j@7W@KPsaA06yC}v?`U`SyIX3%8xTggxa5=IceeDpK&
zb5r$;5(_dCQ*-n~GE$2(i}edKQsN5}i*gg=i&GPe@=Hrni}jQ9Q&RN<DoZl*^Yn|e
p6ElnTOG`3yiuL2;GxIV_;^XxSDsOSv<mRW8=A_zzZ21gw4FH}9DbxS}
diff --git a/skais/utils/__pycache__/geography.cpython-38.pyc b/skais/utils/__pycache__/geography.cpython-38.pyc
deleted file mode 100644
index 4c93677db8d3da9f08059537b93a7a25c1f32d7d..0000000000000000000000000000000000000000
GIT binary patch
literal 0
HcmV?d00001
literal 746
zcmWIL<>g{vU|`_ZN=}qvVqka-;vi#Y1_lNP1_p*=GX@5R6owSW9EM!RC`LvQn<<AW
ziaCWLg*k^Mmo<u&ks*~eg(ZcxmobGcg}sHLnK6njg(;Xplj9}GL`}w9!WoHWsYS(^
zd8zR!nZ+fEdC958ewvK8n6olVLNpm~apdI}RF-7q=Owd%bU-m50|NsG0|SFI$QfH0
z7#K<z7BJQ@EM%-@0kfDEGS;$!S&R!AYuUgo=7o&4>?w@395rk;ED{X0oHgt<tP%{h
zTqO((m})pvn4}pNG9t4@K&CR+uz*FGYuFYtf<>5WxFBlLdEyMU+$l^Y3=2SRV6EW>
z>tjt}uHlwoSjf1LNra)6r-q}3M}(o4w}v;EL6gNVbB9?X!%HRx28Nf63=9mKY`2*5
z3U09%C8lI1<`v&!F3!xm#hjd9e2YD?D7hpt&*&CQabZ!3Cf_ZVoWv4CFlls)H77qW
z-4H?<-D0XRyv0;$c#EmR=oV9@(JjWHTkI*RIVFkl6);BSEyl!KjLEkcQ&ut*Ni#4o
z{PNY$$j?pHFG?)PNKDPq56MU^&Mek1$ViDVOf1Sxj4w`2EXpq}NiEh-&QD3z4**Ar
zesOkUX0d*0NoG#5etK$tI!Jq^UP0w8p7f&B#FF^r%%bF+R8~+V$$?^yiHi{onOK-O
z7&(}97<v9PG4lLpV^(0|U@Vdag#de$L~(XbYGP5IUT$hhQD$<nUO{4JQF&%@Y7r=$
zZn5T-<`z^Iu`@6*fZ0ijMW6%;)(!Rx5+MUp#9@=0pHiBWY6lA8Vo<8#VdP-sVd7u}
E0ICYU>i_@%
diff --git a/skais/utils/geography.py b/skais/utils/geography.py
index 82c5fa4..a45ec84 100644
--- a/skais/utils/geography.py
+++ b/skais/utils/geography.py
@@ -2,6 +2,9 @@ from sklearn.metrics.pairwise import haversine_distances
import numpy as np
from numba import jit
+R = 6371000
+
+
@jit(nopython=True)
def great_circle(lat1, lat2, long1, long2):
x1 = np.radians(lat1)
@@ -9,10 +12,8 @@ def great_circle(lat1, lat2, long1, long2):
x2 = np.radians(lat2)
y2 = np.radians(long2)
- R = 6371000
-
delta_x = x2 - x1
- delta_y= y2 -y1
+ delta_y = y2 - y1
a = np.sin(delta_x / 2) * np.sin(delta_x / 2) + np.cos(x1) * np.cos(x2) * \
np.sin(delta_y / 2) * np.sin(delta_y / 2)
@@ -21,3 +22,16 @@ def great_circle(lat1, lat2, long1, long2):
d = R * c
return d
+
+
+def position_from_distance(position, distances):
+ lat = np.arcsin(
+ np.sin(np.radians(position[0])) * np.cos(distances[0] / R) + np.cos(np.radians(position[0])) * np.sin(
+ distances[0] / R))
+
+ long = np.radians(position[1]) + np.arctan2(
+ np.sin(distances[1] / R) * np.cos(np.radians(position[0])),
+ np.cos(distances[1] / R) - (np.sin(np.radians(position[1])) * np.sin(lat))
+ )
+
+ return np.degrees(lat), np.degrees(long)
--
GitLab