Fixed a bug in getParallacticAngle(): atan2 instead of atan (0dfc0c18) · Commits · INAF / DISCOS

Common/Servers/DewarPositioner/src/DewarPositioner/posgenerator.py

+2 −3

Original line number	Diff line number	Diff line
		"""This module implements the position generators"""
		import datetime
		import time
		from math import sin, cos, tan, atan, degrees
		from math import sin, cos, tan, atan2, degrees
		from IRAPy import logger
		from Acspy.Common.TimeHelper import getTimeStamp

		@@ -54,8 +54,7 @@ class PosGenerator(object):
		@staticmethod
		def getParallacticAngle(latitude, az, el):
		"""Arguments in radians"""
		tan_p = - sin(az) / (tan(latitude)cos(el) - sin(el)cos(az))
		p = atan(tan_p)
		p = atan2(-sin(az), tan(latitude)cos(el) - sin(el)cos(az))
		return degrees(p)

Common/Servers/DewarPositioner/src/DewarPositioner/positioner.py

+1 −1

Original line number	Diff line number	Diff line
		@@ -536,7 +536,7 @@ class Positioner(object):
		def _start(self, posgen, *vargs):
		"""Start a new process that computes and sets the position"""
		if self.isSetup():
		self.stopUpdating() # Raise a PositionerError if the process stills alive
		# self.stopUpdating() # Raise a PositionerError if the process stills alive
		self.t = ContainerServices.ContainerServices().getThread(
		name=posgen.__name__,
		target=self._updatePosition,

Common/Servers/DewarPositioner/test/pyunit/posgen/test_parallactic.py

+10 −20

Original line number	Diff line number	Diff line
		import unittest2
		import mocker
		from math import sin, cos, tan, atan, radians, degrees, pi
		from math import sin, cos, tan, atan, radians, degrees, pi, atan2
		from DewarPositioner.posgenerator import PosGenerator, PosGeneratorError


		@@ -31,20 +31,6 @@ class PosGeneratorParallacticTest(unittest2.TestCase):
		gen = self.posgen.parallactic(source, siteInfo={'latitude': 39})
		self.assertRaises(PosGeneratorError, gen.next)

		def test_zero_division_timeout(self):
		"""Raise a PosGeneratorError if case of countinuos zero division"""
		source = self.m.mock()
		mocker.expect(
		source.getRawCoordinates(mocker.ANY)
		).result((90, 0))
		self.m.count(1, None)
		self.m.count(1, None)
		self.m.count(1, None)
		self.m.count(1, None)
		self.m.replay()
		gen = self.posgen.parallactic(source, siteInfo={'latitude': 0})
		self.assertRaises(PosGeneratorError, gen.next)

		def test_right_behavior(self):
		"""Generate 3 positions and do not stop in case of isolated zero div"""
		azimuths = (45, 45, 90, 45)
		@@ -62,13 +48,17 @@ class PosGeneratorParallacticTest(unittest2.TestCase):
		for azd, eld in zip(azimuths, elevations):
		az = radians(azd)
		el = radians(eld)
		try:
		tan_p = - sin(az) / (tan(latitude)cos(el) - sin(el)cos(az))
		p = atan(tan_p)
		except ZeroDivisionError:
		continue
		p = atan2(-sin(az), (tan(latitude)cos(el) - sin(el)cos(az)))
		self.assertEqual(degrees(p), gen.next())

		def test_parallactic_greater_than_90(self):
		"""Verify the (abs) parallactic angle can be greater than 90 degrees"""
		lat = 0.68940505453776013 # 39.5 degrees
		az = 6.1086523819801535 # 350 degrees
		el = 1.2217304763960306 # 70 degrees
		# The related parallactic angle must be 165 degrees
		parallactic = PosGenerator.getParallacticAngle(lat, az, el)
		self.assertGreater(abs(parallactic), 90)

		if __name__ == '__main__':
		unittest2.main()

Common/Servers/DewarPositioner/test/pyunit/positioner/test_getScanInfo.py

+8 −6

Original line number	Diff line number	Diff line
		from __future__ import with_statement
		import unittest2
		import random
		import math
		import time

		import Management
		@@ -33,12 +34,13 @@ class PositionerStartUpdatingTest(unittest2.TestCase):
		def test_updating(self):
		self.cdbconf.setup('KKG')
		self.cdbconf.setConfiguration('CUSTOM')
		site_info = {'latitude': 50}
		latitude = az = el = math.radians(50)
		site_info = {'latitude': latitude}
		self.p.setup(site_info, self.source, self.device)
		posgen = PosGenerator()
		gen = posgen.parallactic(self.source, site_info)
		self.assertEqual(self.p.getScanInfo()['axis'], Management.MNG_NO_AXIS)
		self.p.startUpdating(Management.MNG_TRACK, Antenna.ANT_NORTH, 60, 60)
		self.p.startUpdating(Management.MNG_TRACK, Antenna.ANT_NORTH, az, el)
		self.assertEqual(self.p.getScanInfo()['axis'], Management.MNG_TRACK)
		self.p.stopUpdating()
		self.assertEqual(self.p.getScanInfo()['axis'], Management.MNG_NO_AXIS)
		@@ -53,10 +55,10 @@ class PositionerStartUpdatingTest(unittest2.TestCase):
		def test_Pip(self):
		self.cdbconf.setup('KKG')
		self.cdbconf.setConfiguration('BSC')
		latitude = 50
		latitude = math.radians(50)
		site_info = {'latitude': latitude}
		self.p.setup(site_info, self.source, self.device)
		az, el = 60, 60
		az = el = math.radians(60)
		Pip = PosGenerator.getParallacticAngle(latitude, az, el)
		self.p.startUpdating(Management.MNG_TRACK, Antenna.ANT_NORTH, az, el)
		self.assertEqual(self.p.getScanInfo()['iStaticPos'], -19.2)
		@@ -65,12 +67,12 @@ class PositionerStartUpdatingTest(unittest2.TestCase):
		def test_Pdp(self):
		self.cdbconf.setup('KKG')
		self.cdbconf.setConfiguration('CUSTOM')
		latitude = 50
		latitude = az = el = math.radians(50)
		site_info = {'latitude': latitude}
		self.p.setup(site_info, self.source, self.device)
		posgen = PosGenerator()
		gen = posgen.parallactic(self.source, site_info)
		self.p.startUpdating(Management.MNG_TRACK, Antenna.ANT_NORTH, 50, 50)
		self.p.startUpdating(Management.MNG_TRACK, Antenna.ANT_NORTH, az, el)
		self.assertEqual(self.p.getScanInfo()['axis'], Management.MNG_TRACK)
		self.p.stopUpdating()
		self.assertEqual(self.p.getScanInfo()['axis'], Management.MNG_NO_AXIS)

Common/Servers/DewarPositioner/test/pyunit/positioner/test_offset.py

+1 −0

Original line number	Diff line number	Diff line
		@@ -70,6 +70,7 @@ class PositionerOffsetTest(unittest2.TestCase):
		max_limit = self.device.getMaxLimit()
		min_limit = self.device.getMinLimit()
		Pis = max_limit - offset/2
		time.sleep(0.2) if self.using_mock else time.sleep(3)
		self.p.setPosition(Pis)
		time.sleep(0.2) # Wait a bit for the setup
		max_rewinding_steps = (max_limit - min_limit) // self.device.getStep()