python-ecosys/suntime: add new module

lorcap · lorcap · commit c47a665023cf · 2021-09-27T14:30:52.000+02:00
Signed-off-by: Lorenzo Cappelletti &lt;lorenzo.cappelletti@gmail.com&gt;
diff --git a/python-ecosys/suntime/example.py b/python-ecosys/suntime/example.py
@@ -0,0 +1,55 @@
+import suntime
+
+Rome     = suntime.Sun( 41.902782 , 12.496366 )
+Warsaw   = suntime.Sun( 51.21     , 21.01     )
+CapeTown = suntime.Sun(-33.9252192, 18.4240762)
+
+dt1 = (2000, 1, 1)
+sr1 = Rome.get_sunrise_time(*dt1) # (6, 38)
+ss1 = Rome.get_sunset_time (*dt1) # (15, 49)
+print('Rome:', sr1, ss1)
+
+dt2 = (2014, 10, 3)
+sr2 = Warsaw.get_sunrise_time(*dt2) # (4, 39)
+ss2 = Warsaw.get_sunset_time (*dt2) # (16, 10)
+print('Warsaw:', sr2, ss2)
+
+dt3 = (2016, 12, 21)
+sr3 = CapeTown.get_sunrise_time(*dt3) # (3, 32)
+ss3 = CapeTown.get_sunset_time (*dt3) # (17, 57)
+print('Cape Town:', sr3, ss3)
+
+#######################################################################
+
+# if `datetime` module is available
+import datetime as datetimelib
+
+timedelta = datetimelib.timedelta
+timezone  = datetimelib.timezone
+datetime  = datetimelib.datetime
+
+utc = timezone.utc
+tz1 = timezone(timedelta(hours=1))
+tz2 = timezone(timedelta(hours=3))
+tz3 = timezone(timedelta(hours=2))
+
+# https://www.timeanddate.com/sun/italy/rome?month=1&year=2000
+print('Rome:')
+rt1 = datetime(*dt1, *sr1, tzinfo=utc).astimezone(tz1) # 2000-01-01 07:38:00+01:00
+st1 = datetime(*dt1, *ss1, tzinfo=utc).astimezone(tz1) # 2000-01-01 16:49:00+01:00
+print('>', rt1)
+print('>', st1)
+
+# https://www.timeanddate.com/sun/poland/warsaw?month=10&year=2014
+print('Warsaw:')
+rt2 = datetime(*dt2, *sr2, tzinfo=utc).astimezone(tz2) # 2014-10-03 07:39:00+03:00
+st2 = datetime(*dt2, *ss2, tzinfo=utc).astimezone(tz2) # 2014-10-03 19:10:00+03:00
+print('>', rt2)
+print('>', st2)
+
+# https://www.timeanddate.com/sun/south-africa/cape-town?month=12&year=2016
+print('Cape Town:')
+rt3 = datetime(*dt3, *sr3, tzinfo=utc).astimezone(tz3) # 2016-12-21 05:32:00+02:00
+st3 = datetime(*dt3, *ss3, tzinfo=utc).astimezone(tz3) # 2016-12-21 19:57:00+02:00
+print('>', rt3)
+print('>', st3)
diff --git a/python-ecosys/suntime/metadata.txt b/python-ecosys/suntime/metadata.txt
@@ -0,0 +1,4 @@
+srctype = cpython
+type = module
+version = 1.0.0
+author = Lorenzo Cappelletti
diff --git a/python-ecosys/suntime/setup.py b/python-ecosys/suntime/setup.py
@@ -0,0 +1,24 @@
+import sys
+
+# Remove current dir from sys.path, otherwise setuptools will peek up our
+# module instead of system's.
+sys.path.pop(0)
+from setuptools import setup
+
+sys.path.append("..")
+import sdist_upip
+
+setup(
+    name="micropython-suntime",
+    version="1.0.0",
+    description="suntime module for MicroPython",
+    long_description="This is a module reimplemented specifically for MicroPython standard library,\nwith efficient and lean design in mind. Note that this module is likely work\nin progress and likely supports just a subset of CPython's corresponding\nmodule. Please help with the development if you are interested in this\nmodule.",
+    url="https://github.com/micropython/micropython-lib",
+    author="micropython-lib Developers",
+    author_email="micro-python@googlegroups.com",
+    maintainer="micropython-lib Developers",
+    maintainer_email="micro-python@googlegroups.com",
+    license="GPL",
+    cmdclass={"sdist": sdist_upip.sdist},
+    py_modules=["suntime"],
+)
diff --git a/python-ecosys/suntime/suntime.py b/python-ecosys/suntime/suntime.py
@@ -0,0 +1,97 @@
+# suntime.py
+
+import math
+
+class Sun:
+    def __init__(self, lat, lon):
+        self._lat = lat
+        self._lon = lon
+
+    def get_sunrise_time(self, year, month, day):
+        return self._calc_sun_time(year, month, day, True)
+
+    def get_sunset_time(self, year, month, day):
+        return self._calc_sun_time(year, month, day, False)
+
+    def _calc_sun_time(self, year, month, day, isRiseTime, zenith=90.8):
+        TO_RAD = math.pi/180.0
+
+        # 1. first calculate the day of the year
+        N1 = math.floor(275 * month / 9)
+        N2 = math.floor((month + 9) / 12)
+        N3 = (1 + math.floor((year - 4 * math.floor(year / 4) + 2) / 3))
+        N = N1 - (N2 * N3) + day - 30
+
+        # 2. convert the longitude to hour value and calculate an approximate time
+        lngHour = self._lon / 15
+
+        if isRiseTime:
+            t = N + ((6 - lngHour) / 24)
+        else: #sunset
+            t = N + ((18 - lngHour) / 24)
+
+        # 3. calculate the Sun's mean anomaly
+        M = (0.9856 * t) - 3.289
+
+        # 4. calculate the Sun's true longitude
+        L = M + (1.916 * math.sin(TO_RAD*M)) + (0.020 * math.sin(TO_RAD * 2 * M)) + 282.634
+        L = self._force_range(L, 360 ) #NOTE: L adjusted into the range [0,360)
+
+        # 5a. calculate the Sun's right ascension
+
+        RA = (1/TO_RAD) * math.atan(0.91764 * math.tan(TO_RAD*L))
+        RA = self._force_range(RA, 360 ) #NOTE: RA adjusted into the range [0,360)
+
+        # 5b. right ascension value needs to be in the same quadrant as L
+        Lquadrant  = (math.floor( L/90)) * 90
+        RAquadrant = (math.floor(RA/90)) * 90
+        RA = RA + (Lquadrant - RAquadrant)
+
+        # 5c. right ascension value needs to be converted into hours
+        RA = RA / 15
+
+        # 6. calculate the Sun's declination
+        sinDec = 0.39782 * math.sin(TO_RAD*L)
+        cosDec = math.cos(math.asin(sinDec))
+
+        # 7a. calculate the Sun's local hour angle
+        cosH = (math.cos(TO_RAD*zenith) - (sinDec * math.sin(TO_RAD*self._lat))) / (cosDec * math.cos(TO_RAD*self._lat))
+
+        if cosH > 1:
+            return None     # The sun never rises on this location (on the specified date)
+        if cosH < -1:
+            return None     # The sun never sets on this location (on the specified date)
+
+        # 7b. finish calculating H and convert into hours
+
+        if isRiseTime:
+            H = 360 - (1/TO_RAD) * math.acos(cosH)
+        else: #setting
+            H = (1/TO_RAD) * math.acos(cosH)
+
+        H = H / 15
+
+        #8. calculate local mean time of rising/setting
+        T = H + RA - (0.06571 * t) - 6.622
+
+        #9. adjust back to UTC
+        UT = T - lngHour
+        UT = self._force_range(UT, 24)   # UTC time in decimal format (e.g. 23.23)
+
+        #10. Return
+        hr = self._force_range(int(UT), 24)
+        min = round((UT - int(UT))*60)
+        if min == 60:
+            min = 0
+            hr = self._force_range(hr + 1, 24)
+
+        return hr, min
+
+    def _force_range(self, v, max):
+        # force v to be >= 0 and < max
+        if v < 0:
+            return v + max
+        elif v >= max:
+            return v - max
+
+        return v
diff --git a/python-ecosys/suntime/test_suntime.py b/python-ecosys/suntime/test_suntime.py
@@ -0,0 +1,35 @@
+# test_suntime.py
+
+import unittest
+import suntime
+
+Rome     = suntime.Sun( 41.902782 , 12.496366 )
+Warsaw   = suntime.Sun( 51.21     , 21.01     )
+CapeTown = suntime.Sun(-33.9252192, 18.4240762)
+
+dt1 = (2000,  1,  1)
+dt2 = (2014, 10,  3)
+dt3 = (2016, 12, 21)
+
+class TestSunTime(unittest.TestCase):
+
+    def test_sunrise1(self):
+        self.assertEqual(Rome.get_sunrise_time(*dt1), (6, 38))
+
+    def test_sunset1(self):
+        self.assertEqual(Rome.get_sunset_time(*dt1), (15, 49))
+
+    def test_sunrise2(self):
+        self.assertEqual(Warsaw.get_sunrise_time(*dt2),  (4, 39))
+
+    def test_sunset2(self):
+        self.assertEqual(Warsaw.get_sunset_time (*dt2),  (16, 10))
+
+    def test_sunrise3(self):
+        self.assertEqual(CapeTown.get_sunrise_time(*dt3),  (3, 32))
+
+    def test_sunset3(self):
+        self.assertEqual(CapeTown.get_sunset_time (*dt3),  (17, 57))
+
+if __name__ == '__main__':
+        unittest.main()
