Remove incorrect override of pcolor/contour in parasite axes.

anntzer · anntzer · commit b7636496b1e8 · 2020-09-24T13:42:14.000+02:00
The override of `pcolor`, `pcolormesh`, `contour`, and `contourf` in
parasite axes was actually incorrect.  Perhaps things were different
when that code went in, but nowadays things work just fine without any
need for overriding.

See e.g. the new version of demo_curvelinear_grid before and after the
changes.

The default gridding of `pcolor`/`pcolormesh` changed to match the one
of normal Axes; I don't think this is worth going through a deprecation
period...
diff --git a/doc/api/next_api_changes/behavior/18560-AL.rst b/doc/api/next_api_changes/behavior/18560-AL.rst
@@ -0,0 +1,4 @@
+Parasite Axes pcolor and pcolormesh now defaults to placing grid edges at integers, not half-integers
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+This is consistent with `~.Axes.pcolor` and `~.Axes.pcolormesh`.
diff --git a/examples/axisartist/demo_curvelinear_grid.py b/examples/axisartist/demo_curvelinear_grid.py
@@ -109,6 +109,11 @@ def curvelinear_test2(fig):
     ax1.parasites.append(ax2)
     ax2.plot(np.linspace(0, 30, 51), np.linspace(10, 10, 51), linewidth=2)
 
+    ax2.pcolor(np.linspace(0, 90, 4), np.linspace(0, 10, 4),
+               np.arange(9).reshape((3, 3)))
+    ax2.contour(np.linspace(0, 90, 4), np.linspace(0, 10, 4),
+                np.arange(16).reshape((4, 4)), colors="k")
+
 
 if __name__ == "__main__":
     fig = plt.figure(figsize=(7, 4))
diff --git a/lib/mpl_toolkits/axes_grid1/parasite_axes.py b/lib/mpl_toolkits/axes_grid1/parasite_axes.py
@@ -7,8 +7,6 @@
 from matplotlib.transforms import Bbox
 from .mpl_axes import Axes
 
-import numpy as np
-
 
 class ParasiteAxesBase:
 
@@ -108,72 +106,6 @@ def update_viewlim(self):
         else:
             _api.check_in_list([None, "equal", "transform"], mode=mode)
 
-    def _pcolor(self, super_pcolor, *XYC, **kwargs):
-        if len(XYC) == 1:
-            C = XYC[0]
-            ny, nx = C.shape
-
-            gx = np.arange(-0.5, nx)
-            gy = np.arange(-0.5, ny)
-
-            X, Y = np.meshgrid(gx, gy)
-        else:
-            X, Y, C = XYC
-
-        if "transform" in kwargs:
-            mesh = super_pcolor(X, Y, C, **kwargs)
-        else:
-            orig_shape = X.shape
-            xyt = np.column_stack([X.flat, Y.flat])
-            wxy = self.transAux.transform(xyt)
-            gx = wxy[:, 0].reshape(orig_shape)
-            gy = wxy[:, 1].reshape(orig_shape)
-            mesh = super_pcolor(gx, gy, C, **kwargs)
-            mesh.set_transform(self._parent_axes.transData)
-
-        return mesh
-
-    def pcolormesh(self, *XYC, **kwargs):
-        return self._pcolor(super().pcolormesh, *XYC, **kwargs)
-
-    def pcolor(self, *XYC, **kwargs):
-        return self._pcolor(super().pcolor, *XYC, **kwargs)
-
-    def _contour(self, super_contour, *XYCL, **kwargs):
-
-        if len(XYCL) <= 2:
-            C = XYCL[0]
-            ny, nx = C.shape
-
-            gx = np.arange(0., nx)
-            gy = np.arange(0., ny)
-
-            X, Y = np.meshgrid(gx, gy)
-            CL = XYCL
-        else:
-            X, Y = XYCL[:2]
-            CL = XYCL[2:]
-
-        if "transform" in kwargs:
-            cont = super_contour(X, Y, *CL, **kwargs)
-        else:
-            orig_shape = X.shape
-            xyt = np.column_stack([X.flat, Y.flat])
-            wxy = self.transAux.transform(xyt)
-            gx = wxy[:, 0].reshape(orig_shape)
-            gy = wxy[:, 1].reshape(orig_shape)
-            cont = super_contour(gx, gy, *CL, **kwargs)
-            for c in cont.collections:
-                c.set_transform(self._parent_axes.transData)
-
-        return cont
-
-    def contour(self, *XYCL, **kwargs):
-        return self._contour(super().contour, *XYCL, **kwargs)
-
-    def contourf(self, *XYCL, **kwargs):
-        return self._contour(super().contourf, *XYCL, **kwargs)
-
     def apply_aspect(self, position=None):
         self.update_viewlim()
         super().apply_aspect()
