Пример #1
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    def test_against_pyephem(self):
        """Check for consistent results with one PyEphem example.

        PyEphem: http://rhodesmill.org/pyephem/

        See example input and output here:
        https://gist.github.com/zonca/1672906
        https://github.com/phn/pytpm/issues/2#issuecomment-3698679

        """
        # PyEphem
        ra_expected = np.radians(196.497518)
        dec_expected = np.radians(-4.569323)

        # Astropy 1.0rc1
        ra_astropy = np.radians(196.49537283)
        dec_astropy = np.radians(-4.5606942763)

        # Data
        longitude = base.sexagesimal_to_decimal(-109, -24, -53.1)
        latitude = base.sexagesimal_to_decimal(33, 41, 46.0)
        utc = datetime.datetime(2011, 9, 18, 8, 50)
        altitude = np.radians(-60.7665)
        azi = np.radians(6.8927)

        # SAPPHiRE
        gps = clock.utc_to_gps(calendar.timegm(utc.utctimetuple()))
        zenith, azimuth = celestial.horizontal_to_zenithazimuth(altitude, azi)
        ra, dec = celestial.zenithazimuth_to_equatorial(
            longitude, latitude, gps, zenith, azimuth)

        self.assertAlmostEqual(ra, ra_expected, 2)
        self.assertAlmostEqual(ra, ra_astropy, 2)
        self.assertAlmostEqual(dec, dec_expected, 2)
        self.assertAlmostEqual(dec, dec_astropy, 2)
Пример #2
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    def test_against_pyephem(self):
        """Check for consistent results with one PyEphem example.

        PyEphem: http://rhodesmill.org/pyephem/

        See example input and output here:
        https://gist.github.com/zonca/1672906
        https://github.com/phn/pytpm/issues/2#issuecomment-3698679

        """
        # PyEphem
        ra_expected = np.radians(196.497518)
        dec_expected = np.radians(-4.569323)

        # Astropy 1.0rc1
        ra_astropy = np.radians(196.49537283)
        dec_astropy = np.radians(-4.5606942763)

        # Data
        longitude = base.sexagesimal_to_decimal(-109, -24, -53.1)
        latitude = base.sexagesimal_to_decimal(33, 41, 46.0)
        utc = datetime.datetime(2011, 9, 18, 8, 50)
        altitude = np.radians(-60.7665)
        azi = np.radians(6.8927)

        # SAPPHiRE
        gps = clock.utc_to_gps(calendar.timegm(utc.utctimetuple()))
        zenith, azimuth = celestial.horizontal_to_zenithazimuth(altitude, azi)
        ra, dec = celestial.zenithazimuth_to_equatorial(latitude, longitude,
                                                        gps, zenith, azimuth)

        self.assertAlmostEqual(ra, ra_expected, 2)
        self.assertAlmostEqual(ra, ra_astropy, 2)
        self.assertAlmostEqual(dec, dec_expected, 2)
        self.assertAlmostEqual(dec, dec_astropy, 2)
Пример #3
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def test_against_hor2eq():
    """Check that Astropy gives consistent results with an IDL hor2eq example.

    See EXAMPLE input and output here:
    http://idlastro.gsfc.nasa.gov/ftp/pro/astro/hor2eq.pro
    """
    print('IDL hor2eq')
    # Observatory position for `kpno` from here:
    # http://idlastro.gsfc.nasa.gov/ftp/pro/astro/observatory.pro
    location = EarthLocation(lon=Angle('-111d36.0m'),
                             lat=Angle('31d57.8m'),
                             height=2120. * u.m)

    # obstime = Time('2041-12-26 05:00:00')
    obstime = Time(2466879.7083333, format='jd')
    # obstime += TimeDelta(-2, format='sec')

    altaz_frame = AltAz(obstime=obstime, location=location)
    altaz = SkyCoord('264d55m06s 37d54m41s', frame=altaz_frame)

    radec_frame = 'icrs'

    # The following transformation throws a warning about precision problems
    # because the observation date is in the future
    with catch_warnings() as _:
        radec_actual = altaz.transform_to(radec_frame)
    print('Astropy: ', radec_actual)

    radec_expected = SkyCoord('00h13m14.1s  +15d11m0.3s', frame=radec_frame)
    print('Source:  ', radec_expected)
    distance = radec_actual.separation(radec_expected).to('arcsec')
    # print(distance)

    # TODO: why is there a difference of 2.6 arcsec currently?
    # radec_expected = ra=3.30875 deg, dec=15.183416666666666 deg
    # radec_actual = ra=3.3094193224314625 deg, dec=15.183757021354532 deg
    # distance = 2.6285 arcsec
    #     assert distance < 5 * u.arcsec

    # SAPPHiRE
    longitude = -111.6
    latitude = 31.9633
    jd = 2466879.7083333
    elevation = (37, 54, 41)
    azi = (264, 55, 6)
    # lst = clock.gmst_to_lst(clock.juliandate_to_gmst(jd), longitude)
    # Matches  LAST = +03 53 53.6  in the hor2eq.pro
    gps = clock.utc_to_gps(
        calendar.timegm(clock.juliandate_to_utc(jd).utctimetuple()))
    zenith, azimuth = celestial.horizontal_to_zenithazimuth(
        np.radians(base.sexagesimal_to_decimal(*elevation)),
        np.radians(base.sexagesimal_to_decimal(*azi)))
    ra, dec = celestial.zenithazimuth_to_equatorial(longitude, latitude, gps,
                                                    zenith, azimuth)

    print('SAPPHiRE: ra=%f, dec=%f' % (np.degrees(ra), np.degrees(dec)))
Пример #4
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    def test_against_hor2eq(self):
        """Check for consistent results with an IDL hor2eq example.

        See EXAMPLE input and output here:
        http://idlastro.gsfc.nasa.gov/ftp/pro/astro/hor2eq.pro

        Observatory position for ``kpno`` from here:
        http://idlastro.gsfc.nasa.gov/ftp/pro/astro/observatory.pro

        """
        # IDL hor2eq
        ra_expected = np.radians(3.30875)
        dec_expected = np.radians(15.183416666666666)

        # Astropy 1.0rc1
        ra_astropy = np.radians(3.3094193224314625)
        dec_astropy = np.radians(15.183757021354532)

        # KPNO observatory
        longitude = -111.6
        latitude = 31.9633

        # Observation time
        jd = 2466879.7083333

        # Altitude Azimuth
        altitude = (37, 54, 41)
        azi = (264, 55, 6)

        # lst = clock.gmst_to_lst(clock.juliandate_to_gmst(jd), longitude)
        # Matches  LAST = +03 53 53.6  in the hor2eq.pro

        # SAPPHiRE
        utc = calendar.timegm(clock.juliandate_to_utc(jd).utctimetuple())
        gps = clock.utc_to_gps(utc)
        zenith, azimuth = celestial.horizontal_to_zenithazimuth(
            np.radians(base.sexagesimal_to_decimal(*altitude)),
            np.radians(base.sexagesimal_to_decimal(*azi)))
        ra, dec = celestial.zenithazimuth_to_equatorial(latitude, longitude,
                                                        gps, zenith, azimuth)

        # Test eq_to_zenaz merely against IDL
        zencalc, azcalc = celestial.equatorial_to_zenithazimuth(
            latitude, longitude, gps, ra_expected, dec_expected)

        self.assertAlmostEqual(ra, ra_expected, 1)
        self.assertAlmostEqual(ra, ra_astropy, 1)
        self.assertAlmostEqual(dec, dec_expected, 2)
        self.assertAlmostEqual(dec, dec_astropy, 2)

        self.assertAlmostEqual(zencalc, zenith, 1)
        self.assertAlmostEqual(azcalc, azimuth, 2)
Пример #5
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    def test_against_hor2eq(self):
        """Check for consistent results with an IDL hor2eq example.

        See EXAMPLE input and output here:
        http://idlastro.gsfc.nasa.gov/ftp/pro/astro/hor2eq.pro

        Observatory position for ``kpno`` from here:
        http://idlastro.gsfc.nasa.gov/ftp/pro/astro/observatory.pro

        """
        # IDL hor2eq
        ra_expected = np.radians(3.30875)
        dec_expected = np.radians(15.183416666666666)

        # Astropy 1.0rc1
        ra_astropy = np.radians(3.3094193224314625)
        dec_astropy = np.radians(15.183757021354532)

        # KPNO observatory
        longitude = -111.6
        latitude = 31.9633

        # Observation time
        jd = 2466879.7083333

        # Altitude Azimuth
        altitude = (37, 54, 41)
        azi = (264, 55, 6)

        # lst = clock.gmst_to_lst(clock.juliandate_to_gmst(jd), longitude)
        # Matches  LAST = +03 53 53.6  in the hor2eq.pro

        # SAPPHiRE
        utc = calendar.timegm(clock.juliandate_to_utc(jd).utctimetuple())
        gps = clock.utc_to_gps(utc)
        zenith, azimuth = celestial.horizontal_to_zenithazimuth(
            np.radians(base.sexagesimal_to_decimal(*altitude)),
            np.radians(base.sexagesimal_to_decimal(*azi)))
        ra, dec = celestial.zenithazimuth_to_equatorial(
            latitude, longitude, gps, zenith, azimuth)

        # Test eq_to_zenaz merely against IDL
        zencalc, azcalc = celestial.equatorial_to_zenithazimuth(
            latitude, longitude, gps, ra_expected, dec_expected)

        self.assertAlmostEqual(ra, ra_expected, 1)
        self.assertAlmostEqual(ra, ra_astropy, 1)
        self.assertAlmostEqual(dec, dec_expected, 2)
        self.assertAlmostEqual(dec, dec_astropy, 2)

        self.assertAlmostEqual(zencalc, zenith, 1)
        self.assertAlmostEqual(azcalc, azimuth, 2)
Пример #6
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def test_against_pyephem():
    """Check that Astropy gives consistent results with one PyEphem example.

    PyEphem: http://rhodesmill.org/pyephem/

    See example input and output here:
    https://gist.github.com/zonca/1672906
    https://github.com/phn/pytpm/issues/2#issuecomment-3698679
    """
    print('PyEphem')
    obstime = Time('2011-09-18 08:50:00')
    location = EarthLocation(lon=Angle('-109d24m53.1s'),
                             lat=Angle('33d41m46.0s'),
                             height=0. * u.m)
    # We are using the default pressure and temperature in PyEphem
    altaz_frame = AltAz(obstime=obstime, location=location)

    altaz = SkyCoord('6.8927d -60.7665d', frame=altaz_frame)
    radec_actual = altaz.transform_to('icrs')
    print('Astropy: ', radec_actual)

    radec_expected = SkyCoord('196.497518d -4.569323d', frame='icrs')  # EPHEM
    print('Source:  ', radec_expected)
    # radec_expected = SkyCoord('196.496220d -4.569390d', frame='icrs')  # HORIZON
    distance = radec_actual.separation(radec_expected).to('arcsec')
    # TODO: why is this difference so large?
    # It currently is: 31.45187984720655 arcsec
    assert distance < 1e3 * u.arcsec

    # Add assert on current Astropy result so that we notice if something changes
    radec_expected = SkyCoord('196.495372d -4.560694d', frame='icrs')
    distance = radec_actual.separation(radec_expected).to('arcsec')
    # Current value: 0.0031402822944751997 arcsec
    #assert distance < 1 * u.arcsec

    # SAPPHiRE
    longitude = base.sexagesimal_to_decimal(-109, -24, -53.1)
    latitude = base.sexagesimal_to_decimal(33, 41, 46.0)
    utc = datetime.datetime(2011, 9, 18, 8, 50, 00)
    elevation = np.radians(-60.7665)
    azi = np.radians(6.8927)
    gps = clock.utc_to_gps(calendar.timegm(utc.utctimetuple()))
    zenith, azimuth = celestial.horizontal_to_zenithazimuth(elevation, azi)
    ra, dec = celestial.zenithazimuth_to_equatorial(longitude, latitude, gps,
                                                    zenith, azimuth)

    print('SAPPHiRE: ra=%f, dec=%f' % (np.degrees(ra), np.degrees(dec)))
Пример #7
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 def test_sexagesimal_to_decimal(self):
     for dec, sexa in self.combinations:
         self.assertEqual(base.sexagesimal_to_decimal(*sexa), dec)