Update contours operation to work with QuadMesh (#2702)

holoviz · May 21, 2018 · 234a3e4 · 234a3e4
1 parent 18ca8a4
commit 234a3e4
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Showing 2 changed files with 28 additions and 4 deletions.
diff --git a/holoviews/operation/element.py b/holoviews/operation/element.py
@@ -434,9 +434,9 @@ def _process(self, element, key=None):
         elif isinstance(element, Image):
             data = [np.flipud(element.dimension_values(2, flat=False))]
         elif isinstance(element, QuadMesh):
-            data = (element.dimension_values(0, False),
-                    element.dimension_values(1, False),
-                    element.data[2])
+            data = (element.dimension_values(0, False, flat=False),
+                    element.dimension_values(1, False, flat=False),
+                    element.dimension_values(2, flat=False))
 
         if isinstance(self.p.levels, int):
             levels = self.p.levels+2 if self.p.filled else self.p.levels+3

diff --git a/tests/operation/testoperation.py b/tests/operation/testoperation.py
@@ -2,7 +2,8 @@
 from nose.plugins.attrib import attr
 
 from holoviews import (HoloMap, NdOverlay, NdLayout, GridSpace, Image,
-                       Contours, Polygons, Points, Histogram, Curve, Area)
+                       Contours, Polygons, Points, Histogram, Curve, Area,
+                       QuadMesh)
 from holoviews.element.comparison import ComparisonTestCase
 from holoviews.operation.element import (operation, transform, threshold,
                                          gradient, contours, histogram,
@@ -63,6 +64,29 @@ def test_image_contours(self):
                             vdims=img.vdims)
         self.assertEqual(op_contours, contour)
 
+    @attr(optional=1) # Requires matplotlib
+    def test_qmesh_contours(self):
+        qmesh = QuadMesh(([0, 1, 2], [1, 2, 3], np.array([[0, 1, 0], [3, 4, 5.], [6, 7, 8]])))
+        op_contours = contours(qmesh, levels=[0.5])
+        contour = Contours([[(0,  1.166667, 0.5), (0.5, 1., 0.5),
+                             (np.NaN, np.NaN, 0.5), (1.5, 1., 0.5),
+                             (2, 1.1, 0.5)]],
+                            vdims=qmesh.vdims)
+        self.assertEqual(op_contours, contour)
+
+    @attr(optional=1) # Requires matplotlib
+    def test_qmesh_curvilinear_contours(self):
+        x = y = np.arange(3)
+        xs, ys = np.meshgrid(x, y)
+        zs = np.array([[0, 1, 0], [3, 4, 5.], [6, 7, 8]])
+        qmesh = QuadMesh((xs, ys+0.1, zs))
+        op_contours = contours(qmesh, levels=[0.5])
+        contour = Contours([[(0,  0.266667, 0.5), (0.5, 0.1, 0.5),
+                             (np.NaN, np.NaN, 0.5), (1.5, 0.1, 0.5),
+                             (2, 0.2, 0.5)]],
+                            vdims=qmesh.vdims)
+        self.assertEqual(op_contours, contour)
+
     @attr(optional=1) # Requires matplotlib
     def test_image_contours_filled(self):
         img = Image(np.array([[0, 1, 0], [3, 4, 5.], [6, 7, 8]]))