scatter plot and hexbin plot lose x-axis when colorbar is included.

pandas/plotting/_core.py

@@ -870,6 +870,7 @@ def _make_plot(self):
         scatter = ax.scatter(data[x].values, data[y].values, c=c_values,
                              label=label, cmap=cmap, **self.kwds)
         if cb:
+            ax._pandas_colorbar_axes = True
             img = ax.collections[0]
             kws = dict(ax=ax)
             if self.mpl_ge_1_3_1():
@@ -902,6 +903,7 @@ def __init__(self, data, x, y, C=None, **kwargs):
     def _make_plot(self):
         x, y, data, C = self.x, self.y, self.data, self.C
         ax = self.axes[0]
+
         # pandas uses colormap, matplotlib uses cmap.
         cmap = self.colormap or 'BuGn'
         cmap = self.plt.cm.get_cmap(cmap)
@@ -915,6 +917,7 @@ def _make_plot(self):
         ax.hexbin(data[x].values, data[y].values, C=c_values, cmap=cmap,
                   **self.kwds)
         if cb:
+            ax._pandas_colorbar_axes = True
             img = ax.collections[0]
             self.fig.colorbar(img, ax=ax)
 
@@ -2790,6 +2793,7 @@ def __call__(self, x=None, y=None, kind='line', ax=None,
                  rot=None, fontsize=None, colormap=None, table=False,
                  yerr=None, xerr=None,
                  secondary_y=False, sort_columns=False, **kwds):
+
         return plot_frame(self._data, kind=kind, x=x, y=y, ax=ax,
                           subplots=subplots, sharex=sharex, sharey=sharey,
                           layout=layout, figsize=figsize, use_index=use_index,
@@ -3286,6 +3290,7 @@ def scatter(self, x, y, s=None, c=None, **kwds):
             ...                       c='species',
             ...                       colormap='viridis')
         """
+
         return self(kind='scatter', x=x, y=y, c=c, s=s, **kwds)
 
     def hexbin(self, x, y, C=None, reduce_C_function=None, gridsize=None,
@@ -3371,6 +3376,7 @@ def hexbin(self, x, y, C=None, reduce_C_function=None, gridsize=None,
             ...                     gridsize=10,
             ...                     cmap="viridis")
         """
+
         if reduce_C_function is not None:
             kwds['reduce_C_function'] = reduce_C_function
         if gridsize is not None:

pandas/plotting/_tools.py

@@ -311,7 +311,7 @@ def _handle_shared_axes(axarr, nplots, naxes, nrows, ncols, sharex, sharey):
                     # only the last row of subplots should get x labels -> all
                     # other off layout handles the case that the subplot is
                     # the last in the column, because below is no subplot/gap.
-                    if not layout[ax.rowNum + 1, ax.colNum]:
+                    if not layout[ax.rowNum + 1, ax.colNum] or getattr(ax, '_pandas_colorbar_axes', False):
                         continue
                     if sharex or len(ax.get_shared_x_axes()
                                      .get_siblings(ax)) > 1: