Exemplo n.º 1
0
    def test_create_vis_iter_with_model(self):
        model = create_test_image(canonical=True,
                                  cellsize=0.001,
                                  frequency=self.frequency,
                                  phasecentre=self.phasecentre)
        comp = Skycomponent(direction=self.phasecentre,
                            frequency=self.frequency,
                            flux=self.flux,
                            polarisation_frame=PolarisationFrame('stokesI'))
        vis_iter = create_blockvisibility_iterator(
            self.config,
            self.times,
            self.frequency,
            channel_bandwidth=self.channel_bandwidth,
            phasecentre=self.phasecentre,
            weight=1.0,
            polarisation_frame=PolarisationFrame('stokesI'),
            integration_time=30.0,
            number_integrations=3,
            model=model,
            components=comp)

        fullvis = None
        totalnvis = 0
        for i, vis in enumerate(vis_iter):
            assert vis.phasecentre == self.phasecentre
            assert vis.nvis
            if i == 0:
                fullvis = vis
                totalnvis = vis.nvis
            else:
                fullvis = append_visibility(fullvis, vis)
                totalnvis += vis.nvis

        assert fullvis.nvis == totalnvis
Exemplo n.º 2
0
    def ingest(self):
        vis = None
        for iv, subvis in enumerate(self.blockvis):
            if iv == 0:
                vis = subvis
            else:
                vis = append_visibility(vis, subvis)

        return vis
Exemplo n.º 3
0
 def test_append_visibility(self):
         self.vis = create_visibility(self.lowcore, self.times, self.frequency,
                                      channel_bandwidth=self.channel_bandwidth,
                                      phasecentre=self.phasecentre,
                                      weight=1.0)
         othertimes = (numpy.pi / 43200.0) * numpy.arange(300.0, 600.0, 30.0)
         self.othervis = create_visibility(self.lowcore, othertimes, self.frequency,
                                           channel_bandwidth=self.channel_bandwidth,
                                           phasecentre=self.phasecentre,
                                           weight=1.0)
         self.vis = append_visibility(self.vis, self.othervis)
         assert self.vis.nvis == len(self.vis.time)
         assert self.vis.nvis == len(self.vis.frequency)
 def test_create_vis_iter(self):
     vis_iter = create_blockvisibility_iterator(self.config, self.times, self.frequency,
                                                channel_bandwidth=self.channel_bandwidth,
                                                phasecentre=self.phasecentre,
                                                weight=1.0, polarisation_frame=PolarisationFrame('stokesI'),
                                                integration_time=30.0, number_integrations=3)
     
     fullvis = None
     totalnvis = 0
     for i, vis in enumerate(vis_iter):
         assert vis.nvis
         if i == 0:
             fullvis = vis
             totalnvis = vis.nvis
         else:
             fullvis = append_visibility(fullvis, vis)
             totalnvis += vis.nvis
     
     assert fullvis.nvis == totalnvis
Exemplo n.º 5
0
        if channel == 0:
            ionRM1, times1, time_indices1 = get_ion_rotation_measures(
                vis1, INPUTS_DIR, MS1)
            ionRM2, times2, time_indices2 = get_ion_rotation_measures(
                vis2, INPUTS_DIR, MS2)
            # Save the median Faraday rotation to disk, as an instrumental estimate:
            np.savetxt('%s/ionFR.txt' % (RESULTS_DIR), \
                       [np.median(np.concatenate((ionRM1, ionRM2), axis=0))], fmt="%s")
        # Correct the data for the ionospheric rotation measure:
        vis1 = correct_ion_faraday(vis1, ionRM1, times1, time_indices1)
        vis2 = correct_ion_faraday(vis2, ionRM2, times2, time_indices2)

    # Prepare Measurement Set
    # ------------------------------------------------------
    # Combine MSSS snapshots:
    vis = append_visibility(vis1, vis2)

    # Apply a uv-distance cut to the data:
    vis = uv_cut(vis, UV_CUTOFF)
    npixel_advice, cell_advice = uv_advice(vis, UV_CUTOFF, PIXELS_PER_BEAM)

    # Make some basic plots:
    if MAKE_PLOTS:
        uv_cov(vis)
        uv_dist(vis)

    # Primary Beam Correction
    # ------------------------------------------------------
    # Apply the primary beam of the instrument:
    if APPLY_BEAM:
        beams = beam_me_up(