Added XArray multi-dimensional coordinate validation

holoviews/core/data/xarray.py

@@ -115,6 +115,27 @@ def init(cls, eltype, data, kdims, vdims):
         return data, {'kdims': kdims, 'vdims': vdims}, {}
 
 
+    @classmethod
+    def validate(cls, dataset, vdims=True):
+        Interface.validate(dataset, vdims)
+        # Check whether irregular (i.e. multi-dimensional) coordinate
+        # array dimensionality matches
+        irregular = []
+        for kd in dataset.kdims:
+            if cls.irregular(dataset, kd):
+                irregular.append((kd, dataset.data[kd.name].dims))
+        if irregular:
+            nonmatching = ['%s: %s' % (kd, dims) for kd, dims in irregular[1:]
+                           if dims != irregular[0][1]]
+            if nonmatching:
+                nonmatching = ['%s: %s' % irregular[0]] + nonmatching
+                raise DataError("The dimensions of coordinate arrays "
+                                "on irregular data must match. The "
+                                "following kdims were found to have "
+                                "non-matching array dimensions:\n\n%s"
+                                % ('\n'.join(nonmatching)), cls)
+
+
     @classmethod
     def range(cls, dataset, dimension):
         dim = dataset.get_dimension(dimension, strict=True).name

tests/testbinneddatasets.py

@@ -8,6 +8,7 @@
 
 from holoviews.core.spaces import HoloMap
 from holoviews.core.data import Dataset
+from holoviews.core.data.interface import DataError
 from holoviews.element import Histogram, QuadMesh
 from holoviews.element.comparison import ComparisonTestCase
 
@@ -199,6 +200,19 @@ def test_construct_3d_from_xarray(self):
         self.assertEqual(dataset.dimension_values('z', expanded=False), np.array([0, 1]))
         self.assertEqual(dataset.dimension_values('A'), zs.T.flatten())
 
+    def test_construct_from_xarray_with_invalid_irregular_coordinate_arrays(self):
+        try:
+            import xarray as xr
+        except:
+            raise SkipError("Test requires xarray")
+        zs = np.arange(48*6).reshape(2, 4, 6, 6)
+        da = xr.DataArray(zs, dims=['z', 'y', 'x', 'b'],
+                          coords = {'lat': (('y', 'b'), self.ys),
+                                    'lon': (('y', 'x'), self.xs),
+                                    'z': [0, 1]}, name='A')
+        with self.assertRaises(DataError):
+            Dataset(da, ['z', 'lon', 'lat'])
+
     def test_3d_xarray_with_constant_dim_canonicalized_to_2d(self):
         try:
             import xarray as xr