Norm should be passed to facetgrid too

doc/whats-new.rst

@@ -158,6 +158,9 @@ Bug fixes
 - Fixed sub-optimal performance in certain operations with object arrays (:issue:`1121`).
   By `Yves Delley <https://github.com/burnpanck>`_.
 
+- Fixed a bug whith facetgrid (the ``norm`` keyword was ignored, :issue:`1159`).
+  By `Fabien Maussion <https://github.com/fmaussion>`_.
+
 .. _whats-new.0.8.2:
 
 v0.8.2 (18 August 2016)

xarray/plot/utils.py

@@ -104,7 +104,7 @@ def _color_palette(cmap, n_colors):
 
 def _determine_cmap_params(plot_data, vmin=None, vmax=None, cmap=None,
                            center=None, robust=False, extend=None,
-                           levels=None, filled=True, cnorm=None):
+                           levels=None, filled=True, norm=None):
     """
     Use some heuristics to set good defaults for colorbar and range.
 
@@ -196,10 +196,10 @@ def _determine_cmap_params(plot_data, vmin=None, vmax=None, cmap=None,
         extend = _determine_extend(calc_data, vmin, vmax)
 
     if levels is not None:
-        cmap, cnorm = _build_discrete_cmap(cmap, levels, extend, filled)
+        cmap, norm = _build_discrete_cmap(cmap, levels, extend, filled)
 
     return dict(vmin=vmin, vmax=vmax, cmap=cmap, extend=extend,
-                levels=levels, norm=cnorm)
+                levels=levels, norm=norm)
 
 
 def _infer_xy_labels(darray, x, y):

xarray/test/test_plot.py

@@ -179,7 +179,8 @@ class TestPlot1D(PlotTestCase):
 
     def setUp(self):
         d = [0, 1.1, 0, 2]
-        self.darray = DataArray(d, coords={'period': range(len(d))})
+        self.darray = DataArray(d, coords={'period': range(len(d))},
+                                dims='period')
 
     def test_xlabel_is_index_name(self):
         self.darray.plot()
@@ -206,7 +207,8 @@ def test_can_pass_in_axis(self):
         self.pass_in_axis(self.darray.plot.line)
 
     def test_nonnumeric_index_raises_typeerror(self):
-        a = DataArray([1, 2, 3], {'letter': ['a', 'b', 'c']})
+        a = DataArray([1, 2, 3], {'letter': ['a', 'b', 'c']},
+                      dims='letter')
         with self.assertRaisesRegexp(TypeError, r'[Pp]lot'):
             a.plot.line()
 
@@ -1032,6 +1034,12 @@ def test_can_set_vmin_vmax(self):
             clim = np.array(image.get_clim())
             self.assertTrue(np.allclose(expected, clim))
 
+    def test_can_set_norm(self):
+        norm = mpl.colors.SymLogNorm(0.1)
+        self.g.map_dataarray(xplt.imshow, 'x', 'y', norm=norm)
+        for image in plt.gcf().findobj(mpl.image.AxesImage):
+            self.assertIs(image.norm, norm)
+
     def test_figure_size(self):
 
         self.assertArrayEqual(self.g.fig.get_size_inches(), (10, 3))