Merge pull request #32 from Cadair/ape14

first pass at using the ape 14 methods on gWCS

changelog/32.trivial.rst

@@ -0,0 +1 @@
+Migrate the `dkist.dataset.Dataset` class to use gWCS's APE 14 API

dkist/dataset/dataset.py

@@ -73,7 +73,7 @@ def __init__(self, data, uncertainty=None, mask=None, wcs=None,
         super().__init__(data, uncertainty, mask, wcs, meta, unit, copy)
 
         if self.wcs and missing_axis is None:
-            self.missing_axis = [False] * self.wcs.forward_transform.n_outputs
+            self.missing_axis = [False] * self.wcs.world_n_dim
         else:
             self.missing_axis = missing_axis
 
@@ -137,9 +137,22 @@ def world_axes_names(self):
         else:
             return ('',) * self.data.ndim  # pragma: no cover  # We should never hit this
 
+    @property
+    def world_axis_physical_types(self):
+        """
+        Returns an iterable of strings describing the physical type for each world axis.
+
+        The strings conform to the International Virtual Observatory Alliance
+        standard, UCD1+ controlled Vocabulary.  For a description of the standard and
+        definitions of the different strings and string components,
+        see http://www.ivoa.net/documents/latest/UCDlist.html.
+
+        """
+        return self.wcs.world_axis_physical_types[::-1]
+
     @property
     def axis_units(self):
-        return self.wcs.output_frame.unit[::-1]
+        return tuple(map(u.Unit, self.wcs.world_axis_units[::-1]))
 
     def __repr__(self):
         """
@@ -175,7 +188,7 @@ def pixel_to_world(self, *quantity_axis_list):
         coord : `list`
             A list of arrays containing the output coordinates.
         """
-        world = self.wcs(*quantity_axis_list[::-1], with_units=True)
+        world = self.wcs.pixel_to_world(*quantity_axis_list[::-1])
 
         # Convert list to tuple as a more standard return type
         if isinstance(world, list):
@@ -205,7 +218,7 @@ def world_to_pixel(self, *quantity_axis_list):
         coord : `list`
             A list of arrays containing the output coordinates.
         """
-        return tuple(self.wcs.invert(*quantity_axis_list[::-1], with_units=True))[::-1]
+        return tuple(self.wcs.world_to_pixel(*quantity_axis_list[::-1]))[::-1]
 
     def world_axis_physical_types(self):
         raise NotImplementedError()  # pragma: no cover
@@ -267,7 +280,7 @@ def crop_by_coords(self, lower_corner, upper_corner, units=None):
         all_world_corners = [all_world_corners_grid[i].flatten()*lower_corner[i].unit
                              for i in range(n_dim)]
         # Convert to pixel coordinates
-        all_pix_corners = self.wcs(*all_world_corners, with_units=False)
+        all_pix_corners = self.wcs.world_to_pixel(*all_world_corners)
         # Derive slicing item with which to slice NDCube.
         # Be sure to round down min pixel and round up + 1 the max pixel.
         item = tuple([slice(int(np.clip(axis_pixels.value.min(), 0, None)),

dkist/dataset/tests/test_dataset.py

@@ -22,7 +22,7 @@ def test_repr(dataset, dataset_3d):
 def test_wcs_roundtrip(dataset):
     p = (10*u.pixel, 10*u.pixel)
     w = dataset.pixel_to_world(*p)
-    p2 = dataset.world_to_pixel(w)
+    p2 = dataset.world_to_pixel(*w)
     assert_quantity_allclose(p, p2)
 
 

dkist/wcs/slicer.py

@@ -6,7 +6,7 @@
 import numpy as np
 
 import gwcs.coordinate_frames as cf
-from astropy.modeling import Model, Parameter, separable
+from astropy.modeling import Model, separable
 from astropy.modeling.models import Shift, Identity
 
 from dkist.utils.model_tools import re_model_trees, remove_input_frame
@@ -22,7 +22,8 @@ def __init__(self, input_specification):
 
     @property
     def inputs(self):
-        return tuple(f"n{i}" for i in range(len(self.input_specification)) if self.input_specification[i] is None)
+        return tuple(f"n{i}" for i in range(len(self.input_specification))
+                     if self.input_specification[i] is None)
 
     @property
     def outputs(self):
@@ -168,7 +169,7 @@ def _new_output_frame(self, axes):
                     start = start[-1]  # pragma: no cover  # I can't work out how to hit this.
                 # Increment start for the next frame.
                 start += 1
-            frame._axes_order = tuple(range(start, start+frame.naxes))
+            frame._axes_order = tuple(range(start, start + frame.naxes))
 
         if len(frames) == 1:
             return frames[0]
@@ -263,11 +264,11 @@ def _convert_item_to_models(self, item, drop_all_non_separable):
                 elif not self.separable[i] and drop_all_non_separable:
                     axes_to_drop.append(i)
                 else:
-                    inputs.append(ax*input_units[i])
+                    inputs.append(ax * input_units[i])
                     prepend.append(Identity(1))
             elif ax.start:
                 inputs.append(None)
-                prepend.append(Shift(ax.start*input_units[i]))
+                prepend.append(Shift(ax.start * input_units[i]))
             else:
                 inputs.append(None)
                 prepend.append(Identity(1))
@@ -310,7 +311,6 @@ def __getitem__(self, item):
                                        remove_coupled_trees=drop_all_non_separable)
             model = re_model_trees(trees)
 
-
         if not all([isinstance(a, Identity) for a in prepend]):
             model = self._list_to_compound(prepend) | model
 

setup.cfg

@@ -40,7 +40,7 @@ exclude = extern,sphinx,*parsetab.py
 
 [flake8]
 max-line-length = 100
-ignore = I100,I102,I103,I104,I201
+ignore = I100,I101,I102,I103,I104,I201
 
 [yapf]
 column_limit = 100