Fix Cubeviz coordinates panel with inaccurate sky coordinates sometimes

CHANGES.rst

@@ -7,6 +7,8 @@ New Features
 Cubeviz
 ^^^^^^^
 
+- Moment map output now has celestial WCS, when applicable. [#2002]
+
 Imviz
 ^^^^^
 
@@ -43,6 +45,11 @@ Bug Fixes
 Cubeviz
 ^^^^^^^
 
+- Fixed a bug where sky coordinates reported to coordinates info panel
+  might be wrong for "uncert" and "mask" data. This bug only happens when
+  certain parsing conditions were met. When in doubt, always verify with
+  info from "flux" data. [#2002]
+
 Imviz
 ^^^^^
 

jdaviz/configs/cubeviz/plugins/moment_maps/moment_maps.py

@@ -3,6 +3,7 @@
 
 from astropy import units as u
 from astropy.nddata import CCDData
+from astropy.wcs import WCS
 
 from traitlets import Unicode, Bool, observe
 from specutils import Spectrum1D, manipulation, analysis
@@ -103,7 +104,14 @@ def calculate_moment(self, add_data=True):
         # Need transpose to align JWST mirror shape. Not sure why.
         # TODO: WCS can be grabbed from cube.wcs[:, :, 0] but CCDData will not take it.
         #       But if we use NDData, glue-astronomy translator fails.
-        self.moment = CCDData(analysis.moment(slab, order=n_moment).T)
+        data = self.dataset.selected_dc_item
+        if isinstance(data.coords, WCS):
+            kwargs = {'wcs': data.coords.celestial}
+        elif isinstance(data.meta.get('_orig_wcs', None), WCS):
+            kwargs = {'wcs': data.meta['_orig_wcs'].celestial}
+        else:
+            kwargs = {}
+        self.moment = CCDData(analysis.moment(slab, order=n_moment).T, **kwargs)
 
         fname_label = self.dataset_selected.replace("[", "_").replace("]", "")
         self.filename = f"moment{n_moment}_{fname_label}.fits"

jdaviz/configs/cubeviz/plugins/moment_maps/tests/test_moment_maps.py

@@ -3,6 +3,7 @@
 import pytest
 from astropy.io import fits
 from astropy.nddata import CCDData
+from astropy.wcs import WCS
 from numpy.testing import assert_allclose
 
 from jdaviz.configs.cubeviz.plugins.moment_maps.moment_maps import MomentMap
@@ -36,7 +37,7 @@ def test_moment_calculation(cubeviz_helper, spectrum1d_cube, tmpdir):
     assert len(mv_data) == 1
     assert mv_data[0].label == 'moment 0'
 
-    assert len(dc.links) == 8
+    assert len(dc.links) == 14
 
     # label should remain unchanged but raise overwrite warnings
     assert mm.results_label == 'moment 0'
@@ -47,8 +48,8 @@ def test_moment_calculation(cubeviz_helper, spectrum1d_cube, tmpdir):
     assert flux_viewer.state.slices == (0, 0, 1)
     assert flux_viewer.label_mouseover.pixel == 'x=00.0 y=00.0'
     assert flux_viewer.label_mouseover.value == '+8.00000e+00 Jy'  # Slice 0 has 8 pixels, this is Slice 1  # noqa
-    assert flux_viewer.label_mouseover.world_ra_deg == '204.9997755346'
-    assert flux_viewer.label_mouseover.world_dec_deg == '27.0000999998'
+    assert flux_viewer.label_mouseover.world_ra_deg == '204.9998877673'
+    assert flux_viewer.label_mouseover.world_dec_deg == '27.0001000000'
 
     # Make sure adding it to viewer does not crash.
     cubeviz_helper.app.add_data_to_viewer(
@@ -57,16 +58,14 @@ def test_moment_calculation(cubeviz_helper, spectrum1d_cube, tmpdir):
 
     result = dc[1].get_object(cls=CCDData)
     assert result.shape == (4, 2)  # Cube shape is (2, 2, 4)
-
-    # FIXME: Need spatial WCS, see https://github.com/spacetelescope/jdaviz/issues/1025
-    assert dc[1].coords is None
+    assert isinstance(dc[1].coords, WCS)
 
     # Make sure coordinate display now show moment map info (no WCS)
     flux_viewer.on_mouse_or_key_event({'event': 'mousemove', 'domain': {'x': 0, 'y': 0}})
     assert flux_viewer.label_mouseover.pixel == 'x=00.0 y=00.0'
     assert flux_viewer.label_mouseover.value == '+8.00000e+00 Jy'  # Slice 0 has 8 pixels, this is Slice 1  # noqa
-    assert flux_viewer.label_mouseover.world_ra_deg == '204.9997755346'
-    assert flux_viewer.label_mouseover.world_dec_deg == '27.0000999998'
+    assert flux_viewer.label_mouseover.world_ra_deg == '204.9998877673'
+    assert flux_viewer.label_mouseover.world_dec_deg == '27.0001000000'
 
     assert mm.filename == 'moment0_test_FLUX.fits'  # Auto-populated on calculate.
     mm.filename = str(tmpdir.join(mm.filename))  # But we want it in tmpdir for testing.
@@ -80,26 +79,15 @@ def test_moment_calculation(cubeviz_helper, spectrum1d_cube, tmpdir):
 
     assert dc[2].label == 'moment 1'
 
-    assert len(dc.links) == 10
-    assert len(dc.external_links) == 4
+    assert len(dc.links) == 22
+    assert len(dc.external_links) == 2
     # Link 3D z to 2D x and 3D y to 2D y
 
-    # Link 3:
-    # Pixel Axis 0 [z] from cube.pixel_component_ids[0]
-    # Pixel Axis 1 [x] from plugin.pixel_component_ids[1]
-    assert dc.external_links[2].cids1[0] == dc[0].pixel_component_ids[0]
-    assert dc.external_links[2].cids2[0] == dc[-1].pixel_component_ids[1]
-    # Link 4:
-    # Pixel Axis 1 [y] from cube.pixel_component_ids[1]
-    # Pixel Axis 0 [y] from plugin.pixel_component_ids[0]
-    assert dc.external_links[3].cids1[0] == dc[0].pixel_component_ids[1]
-    assert dc.external_links[3].cids2[0] == dc[-1].pixel_component_ids[0]
-
     # Coordinate display should be unaffected.
     assert flux_viewer.label_mouseover.pixel == 'x=00.0 y=00.0'
     assert flux_viewer.label_mouseover.value == '+8.00000e+00 Jy'  # Slice 0 has 8 pixels, this is Slice 1  # noqa
-    assert flux_viewer.label_mouseover.world_ra_deg == '204.9997755346'
-    assert flux_viewer.label_mouseover.world_dec_deg == '27.0000999998'
+    assert flux_viewer.label_mouseover.world_ra_deg == '204.9998877673'
+    assert flux_viewer.label_mouseover.world_dec_deg == '27.0001000000'
 
 
 @pytest.mark.filterwarnings('ignore:No observer defined on WCS')
@@ -125,11 +113,16 @@ def test_write_momentmap(cubeviz_helper, spectrum1d_cube, tmp_path):
 
     # We should get an overwrite warning
     assert plugin._obj.overwrite_warn is True
-    # and shouldn't have written anything (the file should be in tact)
+    # and shouldn't have written anything (the file should be intact)
     assert test_file.read_text() == existing_sentinel_text
 
     # Force overwrite the existing file
     plugin._obj.vue_overwrite_fits()
 
     # Read back in the file and check that it is equal to the one we calculated
-    assert_allclose(moment.data, fits.getdata(test_file_str))
+    with fits.open(test_file_str) as pf:
+        assert_allclose(pf[0].data, moment.data)
+        w = WCS(pf[0].header)
+        sky = w.pixel_to_world(0, 0)
+        assert_allclose(sky.ra.deg, 204.99988777)
+        assert_allclose(sky.dec.deg, 27.0001)

jdaviz/configs/cubeviz/plugins/tests/test_parsers.py

@@ -45,11 +45,13 @@ def test_fits_image_hdu_with_microns(image_cube_hdu_obj_microns, cubeviz_helper)
     flux_viewer.on_mouse_or_key_event({'event': 'mousemove', 'domain': {'x': 0, 'y': 0}})
     assert flux_viewer.label_mouseover.pixel == 'x=00.0 y=00.0'
     assert flux_viewer.label_mouseover.value == '+1.00000e+00 1e-17 erg / (Angstrom cm2 s)'
+    # Sky: 205.4398996, 27.00341788
 
     unc_viewer = cubeviz_helper.app.get_viewer('uncert-viewer')
     unc_viewer.on_mouse_or_key_event({'event': 'mousemove', 'domain': {'x': -1, 'y': 0}})
     assert unc_viewer.label_mouseover.pixel == 'x=-1.0 y=00.0'
     assert unc_viewer.label_mouseover.value == ''  # Out of bounds
+    # Sky: 205.43994013, 27.00341788
 
 
 def test_spectrum1d_with_fake_fixed_units(spectrum1d, cubeviz_helper):
@@ -103,15 +105,15 @@ def test_fits_image_hdu_parse_from_file(tmpdir, image_cube_hdu_obj, cubeviz_help
     flux_viewer.on_mouse_or_key_event({'event': 'mousemove', 'domain': {'x': 0, 'y': 0}})
     assert flux_viewer.label_mouseover.pixel == 'x=00.0 y=00.0'
     assert flux_viewer.label_mouseover.value == '+1.00000e+00 1e-17 erg / (Angstrom cm2 s)'
-    assert flux_viewer.label_mouseover.world_ra_deg == '205.4433848390'
-    assert flux_viewer.label_mouseover.world_dec_deg == '26.9996149270'
+    assert flux_viewer.label_mouseover.world_ra_deg == '205.4441642302'
+    assert flux_viewer.label_mouseover.world_dec_deg == '26.9996148973'
 
     unc_viewer = cubeviz_helper.app.get_viewer(cubeviz_helper._default_uncert_viewer_reference_name)
     unc_viewer.on_mouse_or_key_event({'event': 'mousemove', 'domain': {'x': -1, 'y': 0}})
     assert unc_viewer.label_mouseover.pixel == 'x=-1.0 y=00.0'
     assert unc_viewer.label_mouseover.value == ''  # Out of bounds
-    assert unc_viewer.label_mouseover.world_ra_deg == '205.4441642302'
-    assert unc_viewer.label_mouseover.world_dec_deg == '26.9996148973'
+    assert unc_viewer.label_mouseover.world_ra_deg == '205.4443201084'
+    assert unc_viewer.label_mouseover.world_dec_deg == '26.9996148908'
 
 
 @pytest.mark.filterwarnings('ignore')
@@ -131,8 +133,8 @@ def test_spectrum3d_parse(image_cube_hdu_obj, cubeviz_helper):
     flux_viewer.on_mouse_or_key_event({'event': 'mousemove', 'domain': {'x': 0, 'y': 0}})
     assert flux_viewer.label_mouseover.pixel == 'x=00.0 y=00.0'
     assert flux_viewer.label_mouseover.value == '+1.00000e+00 1e-17 erg / (Angstrom cm2 s)'
-    assert flux_viewer.label_mouseover.world_ra_deg == '205.4433848390'
-    assert flux_viewer.label_mouseover.world_dec_deg == '26.9996149270'
+    assert flux_viewer.label_mouseover.world_ra_deg == '205.4441642302'
+    assert flux_viewer.label_mouseover.world_dec_deg == '26.9996148973'
 
     # These viewers have no data.
 

jdaviz/configs/cubeviz/plugins/viewers.py

@@ -1,4 +1,6 @@
 import numpy as np
+from astropy.coordinates import SkyCoord
+from astropy.wcs import WCS
 from glue.core import BaseData
 from glue.core.subset import RoiSubsetState, RangeSubsetState
 from glue_jupyter.bqplot.image import BqplotImageView
@@ -49,6 +51,20 @@ def __init__(self, *args, **kwargs):
         self.add_event_callback(self.on_mouse_or_key_event, events=['mousemove', 'mouseenter',
                                                                     'mouseleave'])
 
+    def _get_cube_skycoord(self, w, x, y):
+        if isinstance(w, WCS):
+            # TODO: Is x always RA and y always DEC?
+            if w.celestial.axis_type_names == ['RA', 'DEC']:
+                sky = w.celestial.pixel_to_world(x, y)
+            else:  # ['DEC', 'RA']
+                sky = w.celestial.pixel_to_world(y, x)
+        else:  # The old and possibly incorrect way
+            sky_list = w.pixel_to_world(x, y, self.state.slices[-1])
+            for sky in sky_list:
+                if isinstance(sky, SkyCoord):
+                    break
+        return sky.icrs
+
     def on_mouse_or_key_event(self, data):
 
         # Find visible layers
@@ -93,18 +109,18 @@ def on_mouse_or_key_event(self, data):
             #  data for this application. This section will need to be updated
             #  when that is no longer true.
             # Hack to insert WCS for generated 2D and 3D images using FLUX cube WCS.
-            if 'Plugin' in image.meta:
+            if 'Plugin' in image.meta and not image.coords:
                 coo_data = self.jdaviz_app.data_collection[0]
             else:
                 coo_data = image
 
             # Hack around various WCS propagation issues in Cubeviz.
             if '_orig_wcs' in coo_data.meta:
-                coo = coo_data.meta['_orig_wcs'].pixel_to_world(x, y, self.state.slices[-1])[0].icrs
+                coo = self._get_cube_skycoord(coo_data.meta['_orig_wcs'], x, y)
                 self.label_mouseover.set_coords(coo)
             elif data_has_valid_wcs(coo_data):
                 try:
-                    coo = coo_data.coords.pixel_to_world(x, y, self.state.slices[-1])[-1].icrs
+                    coo = self._get_cube_skycoord(coo_data.coords, x, y)
                 except Exception:
                     self.label_mouseover.reset_coords_display()
                 else: