test_visibility_operations.py 文件源码

def test_phase_rotation(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)
        # Predict visibilities with new phase centre independently
        ha_diff = -(self.compabsdirection.ra - self.phasecentre.ra).to(u.rad).value
        vispred = create_visibility(self.lowcore, self.times + ha_diff, self.frequency,
                                    channel_bandwidth=self.channel_bandwidth,
                                    phasecentre=self.compabsdirection, weight=1.0,
                                    polarisation_frame=PolarisationFrame("stokesIQUV"))
        vismodel2 = predict_skycomponent_visibility(vispred, self.comp)

        # Should yield the same results as rotation
        rotatedvis = phaserotate_visibility(self.vismodel, newphasecentre=self.compabsdirection, tangent=False)
        assert_allclose(rotatedvis.vis, vismodel2.vis, rtol=1e-7)
        assert_allclose(rotatedvis.uvw, vismodel2.uvw, rtol=1e-7)