test_visibility_operations.py 文件源码

def test_phase_rotation_identity(self):
        self.vis = create_visibility(self.lowcore, self.times, self.frequency,
                                     channel_bandwidth=self.channel_bandwidth,
                                     phasecentre=self.phasecentre, weight=1.0,
                                     polarisation_frame=PolarisationFrame("stokesIQUV"))
        self.vismodel = predict_skycomponent_visibility(self.vis, self.comp)
        newphasecenters = [SkyCoord(182, -35, unit=u.deg), SkyCoord(182, -30, unit=u.deg),
                           SkyCoord(177, -30, unit=u.deg), SkyCoord(176, -35, unit=u.deg),
                           SkyCoord(216, -35, unit=u.deg), SkyCoord(180, -70, unit=u.deg)]
        for newphasecentre in newphasecenters:
            # Phase rotating back should not make a difference
            original_vis = self.vismodel.vis
            original_uvw = self.vismodel.uvw
            rotatedvis = phaserotate_visibility(phaserotate_visibility(self.vismodel, newphasecentre, tangent=False),
                                                self.phasecentre, tangent=False)
            assert_allclose(rotatedvis.uvw, original_uvw, rtol=1e-7)
            assert_allclose(rotatedvis.vis, original_vis, rtol=1e-7)