expose zoom_to_selected in catalogs plugin api

jdaviz/configs/imviz/plugins/catalogs/catalogs.py

@@ -29,6 +29,9 @@ class Catalogs(PluginTemplateMixin, ViewerSelectMixin, HasFileImportSelect, Tabl
     * :meth:`~jdaviz.core.template_mixin.PluginTemplateMixin.show`
     * :meth:`~jdaviz.core.template_mixin.PluginTemplateMixin.open_in_tray`
     * :meth:`~jdaviz.core.template_mixin.PluginTemplateMixin.close_in_tray`
+    * :meth:`~jdaviz.core.template_mixin.PluginTemplateMixin.clear_table`
+    * :meth:`~jdaviz.core.template_mixin.PluginTemplateMixin.export_table`
+    * :meth:`~jdaviz.core.template_mixin.PluginTemplateMixin.zoom_to_selected`
     """
     template_file = __file__, "catalogs.vue"
     uses_active_status = Bool(True).tag(sync=True)
@@ -49,7 +52,8 @@ class Catalogs(PluginTemplateMixin, ViewerSelectMixin, HasFileImportSelect, Tabl
 
     @property
     def user_api(self):
-        return PluginUserApi(self, expose=('clear_table', 'export_table',))
+        return PluginUserApi(self, expose=('clear_table', 'export_table',
+                                           'zoom_to_selected'))
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
@@ -324,23 +328,53 @@ def plot_selected_points(self):
                                                            getattr(y, 'value', y))
 
     def vue_zoom_in(self, *args, **kwargs):
-        """This function will zoom into the image based on the selected points"""
+
+        self.zoom_to_selected(return_bounding_box=True)
+
+    def zoom_to_selected(self, padding=50, return_bounding_box=False):
+        """
+        Zoom to a region containing the currently selected points in the catalog.
+
+        Parameters
+        ----------
+        padding : int, optional
+            The total padding added to the bounding box of the selected points
+            to define the zoom region, in pixels. This value is added to both
+            the minimum and maximum coordinates along each axis. Defaults to 50.
+        return_bounding_box : bool, optional
+            If True, returns the bounding box of the zoomed region as
+            ((x_min, x_max), (y_min, y_max)). Defaults to False.
+
+        Returns
+        -------
+        tuple of tuple, optional
+            If there are activley selected rows, and `return_bounding_box` is
+            True, returns a tuple containing the bounding
+            box coordinates: ((x_min, x_max), (y_min, y_max)).
+            Otherwise, returns None.
+
+        """
+
         selected_rows = self.table.selected_rows
 
+        if not len(selected_rows):
+            return
+
         x = [float(coord['x_coord']) for coord in selected_rows]
         y = [float(coord['y_coord']) for coord in selected_rows]
 
         # this works with single selected points
         # zooming when the range is too large is not performing correctly
-        x_min = min(x) - 50
-        x_max = max(x) + 50
-        y_min = min(y) - 50
-        y_max = max(y) + 50
+        x_min = min(x) - padding
+        x_max = max(x) + padding
+        y_min = min(y) - padding
+        y_max = max(y) + padding
 
         self.app._jdaviz_helper._default_viewer.set_limits(
             x_min=x_min, x_max=x_max, y_min=y_min, y_max=y_max)
 
-        return (x_min, x_max), (y_min, y_max)
+        if return_bounding_box:
+            return (x_min, x_max), (y_min, y_max)
 
     def import_catalog(self, catalog):
         """

jdaviz/configs/imviz/tests/test_catalogs.py

@@ -22,11 +22,12 @@
 '''
 
 import numpy as np
+from numpy.testing import assert_allclose
 import pytest
 
+from astropy.coordinates import SkyCoord
 from astropy.io import fits
 from astropy.nddata import NDData
-from astropy.coordinates import SkyCoord
 from astropy.table import Table, QTable
 
 
@@ -257,3 +258,65 @@ def test_offline_ecsv_catalog(imviz_helper, image_2d_wcs, tmp_path):
     assert imviz_helper.viewers['imviz-0']._obj.state.x_max == 50.00034
     assert imviz_helper.viewers['imviz-0']._obj.state.y_min == -48.99999
     assert imviz_helper.viewers['imviz-0']._obj.state.y_max == 51.00001
+
+
+def test_zoom_to_selected(imviz_helper, image_2d_wcs, tmp_path):
+
+    arr = np.ones((500, 500))
+    ndd = NDData(arr, wcs=image_2d_wcs)
+    imviz_helper.load_data(ndd)
+
+    # write out catalog to file so we can read it back in
+    # todo: if tables can be loaded directly at some point, do that
+
+    # sources at pixel coords ~(100, 100), ~(200, 200)
+    sky_coord = SkyCoord(ra=[337.49056532, 337.46086081],
+                         dec=[-20.80555273, -20.7777673], unit='deg')
+    tbl = Table({'sky_centroid': [sky_coord],
+                 'label': ['Source_1', 'Source_2']})
+    tbl_file = str(tmp_path / 'test_catalog.ecsv')
+    tbl.write(tbl_file, overwrite=True)
+
+    catalogs_plugin = imviz_helper.plugins['Catalog Search']
+
+    catalogs_plugin._obj.from_file = tbl_file
+
+    catalogs_plugin._obj.search()
+
+    # select both sources
+    catalogs_plugin._obj.table.selected_rows = catalogs_plugin._obj.table.items
+
+    # check viewer limits before zoom
+    xmin, xmax, ymin, ymax = imviz_helper.app._jdaviz_helper._default_viewer.get_limits()
+    assert xmin == ymin == -0.5
+    assert xmax == ymax == 499.5
+
+    # zoom to selected sources
+    catalogs_plugin.zoom_to_selected()
+
+    # make sure the viewer bounds reflect the zoom, which, in pixel coords,
+    # should be centered at roughly pixel coords (150, 150)
+    xmin, xmax, ymin, ymax = imviz_helper.app._jdaviz_helper._default_viewer.get_limits()
+
+    assert_allclose((xmin + xmax) / 2, 150., atol=0.1)
+    assert_allclose((ymin + ymax) / 2, 150., atol=0.1)
+
+    # and the zoom box size should reflect the default padding of 50 pixels
+    # added to/subtracted from x(y) min(max)
+    assert_allclose(xmax - xmin, 200., atol=0.1)
+    assert_allclose(ymax - ymin, 200., atol=0.1)
+
+    # select one source now
+    catalogs_plugin._obj.table.selected_rows = catalogs_plugin._obj.table.items[0:1]
+
+    # zoom to single selected source, using a new value for 'padding'
+    catalogs_plugin.zoom_to_selected(padding=25)
+
+    # check that zoom window is centered correctly
+    xmin, xmax, ymin, ymax = imviz_helper.app._jdaviz_helper._default_viewer.get_limits()
+    assert_allclose((xmin + xmax) / 2, 100., atol=0.1)
+    assert_allclose((ymin + ymax) / 2, 100., atol=0.1)
+
+    # and that the the window size corresponds to the 'padding' chosen
+    assert_allclose(xmax - xmin, 50., atol=0.1)
+    assert_allclose(ymax - ymin, 50., atol=0.1)