Set SpikesPlot color index to None by default (#1671)

* Set SpikesPlot color index to None by default

* Set default Spikes colormap to 'fire'

* Updated test_spikes_colormapping unit test

* Minor formatting fix

* Minor whitespace change

holoviews/plotting/bokeh/__init__.py

@@ -139,7 +139,7 @@ def colormap_generator(palette):
 options.Spread = Options('style', color=Cycle(), alpha=0.6, line_color='black')
 options.Bars = Options('style', color=Cycle(), line_color='black', width=0.8)
 
-options.Spikes = Options('style', color='black')
+options.Spikes = Options('style', color='black', cmap='fire')
 options.Area = Options('style', color=Cycle(), line_color='black')
 options.VectorField = Options('style', color='black')
 

holoviews/plotting/bokeh/chart.py

@@ -492,7 +492,7 @@ def get_data(self, element, ranges=None, empty=False):
 
 class SpikesPlot(PathPlot, ColorbarPlot):
 
-    color_index = param.ClassSelector(default=1, allow_None=True,
+    color_index = param.ClassSelector(default=None, allow_None=True,
                                       class_=(basestring, int), doc="""
       Index of the dimension from which the color will the drawn""")
 

holoviews/plotting/mpl/__init__.py

@@ -203,7 +203,7 @@ def grid_selector(grid):
 options.Scatter3D = Options('style', c=Cycle(), marker='o')
 options.Scatter3D = Options('plot', fig_size=150)
 options.Surface = Options('plot', fig_size=150)
-options.Spikes = Options('style', color='black')
+options.Spikes = Options('style', color='black', cmap='fire')
 options.Area = Options('style', facecolor=Cycle(), edgecolor='black')
 options.BoxWhisker = Options('style', boxprops=dict(color='k', linewidth=1.5),
                              whiskerprops=dict(color='k', linewidth=1.5))

holoviews/plotting/mpl/chart.py

@@ -903,7 +903,7 @@ class SpikesPlot(PathPlot, ColorbarPlot):
         explicit aspect ratio as width/height as well as
         'square' and 'equal' options.""")
 
-    color_index = param.ClassSelector(default=1, allow_None=True,
+    color_index = param.ClassSelector(default=None, allow_None=True,
                                       class_=(basestring, int), doc="""
       Index of the dimension from which the color will the drawn""")
 

tests/testplotinstantiation.py

@@ -812,7 +812,8 @@ def test_quadmesh_colormapping(self):
 
     def test_spikes_colormapping(self):
         spikes = Spikes(np.random.rand(20, 2), vdims=['Intensity'])
-        self._test_colormapping(spikes, 1)
+        color_spikes = spikes.opts(plot=dict(color_index=1))
+        self._test_colormapping(color_spikes, 1)
 
     def test_empty_spikes_plot(self):
         spikes = Spikes([], vdims=['Intensity'])