1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
# Copyright Cartopy Contributors
#
# This file is part of Cartopy and is released under the LGPL license.
# See COPYING and COPYING.LESSER in the root of the repository for full
# licensing details.
from datetime import datetime
import pytest
from cartopy.feature.nightshade import _julian_day, _solar_position, Nightshade
def test_julian_day():
# Using Vallado 2007 "Fundamentals of Astrodynamics and Applications"
# Example 3.4
dt = datetime(1996, 10, 26, 14, 20)
jd = _julian_day(dt)
assert pytest.approx(jd) == 2450383.09722222
# Using timeanddate website. Not very many digits of accuracy,
# but it should do OK for simple testing
# 1) Early Sept 2018
# https://www.timeanddate.com/worldclock/sunearth.html
# ?month=9&day=29&year=2018&hour=00&min=00&sec=0&n=&ntxt=&earth=0
# 2) Later Sept 2018
# https://www.timeanddate.com/worldclock/sunearth.html
# ?month=9&day=29&year=2018&hour=14&min=00&sec=0&n=&ntxt=&earth=0
# 3) Different year/month (Feb 1992)
# https://www.timeanddate.com/worldclock/sunearth.html
# ?month=2&day=14&year=1992&hour=00&min=0&sec=0&n=&ntxt=&earth=0
# 4) Test in the future near summer solstice (June 2030)
# https://www.timeanddate.com/worldclock/sunearth.html
# ?month=6&day=21&year=2030&hour=0&min=0&sec=0&n=&ntxt=&earth=0
@pytest.mark.parametrize('dt, true_lat, true_lon', [
(datetime(2018, 9, 29, 0, 0), -(2 + 18 / 60), (177 + 37 / 60)),
(datetime(2018, 9, 29, 14, 0), -(2 + 32 / 60), -(32 + 25 / 60)),
(datetime(1992, 2, 14, 0, 0), -(13 + 20 / 60), -(176 + 26 / 60)),
(datetime(2030, 6, 21, 0, 0), (23 + 26 / 60), -(179 + 34 / 60))
])
def test_solar_position(dt, true_lat, true_lon):
lat, lon = _solar_position(dt)
assert pytest.approx(true_lat, 0.1) == lat
assert pytest.approx(true_lon, 0.1) == lon
def test_nightshade_floating_point():
# Smoke test for clipping nightshade floating point values
date = datetime(1999, 12, 31, 12)
# This can cause an error with floating point precision if it is
# set to exactly -6 and arccos input is not clipped to [-1, 1]
Nightshade(date, refraction=-6.0, color='none')
|
