BUG: timeseries subplots may display unnecessary minor ticklabels

Author: sinhrks

doc/source/v0.15.0.txt

@@ -199,6 +199,7 @@ Bug Fixes
 
 
 
+- Bug in ``DataFrame.plot`` with ``subplots=True`` may draw unnecessary minor xticks and yticks (:issue:`7801`)
 
 
 

pandas/tests/test_graphics.py

@@ -126,11 +126,14 @@ def _check_visible(self, collections, visible=True):
 
         Parameters
         ----------
-        collections : list-like
-            list or collection of target artist
+        collections : matplotlib Artist or its list-like
+            target Artist or its list or collection
         visible : bool
             expected visibility
         """
+        from matplotlib.collections import Collection
+        if not isinstance(collections, Collection) and not com.is_list_like(collections):
+            collections = [collections]
 
         for patch in collections:
             self.assertEqual(patch.get_visible(), visible)
@@ -861,9 +864,12 @@ def test_plot(self):
         axes = _check_plot_works(df.plot, subplots=True, title='blah')
         self._check_axes_shape(axes, axes_num=3, layout=(3, 1))
         for ax in axes[:2]:
+            self._check_visible(ax.xaxis)   # xaxis must be visible for grid
             self._check_visible(ax.get_xticklabels(), visible=False)
+            self._check_visible(ax.get_xticklabels(minor=True), visible=False)
             self._check_visible([ax.xaxis.get_label()], visible=False)
         for ax in [axes[2]]:
+            self._check_visible(ax.xaxis)
             self._check_visible(ax.get_xticklabels())
             self._check_visible([ax.xaxis.get_label()])
 
@@ -1017,21 +1023,61 @@ def test_subplots(self):
                 self._check_legend_labels(ax, labels=[com.pprint_thing(column)])
 
             for ax in axes[:-2]:
+                self._check_visible(ax.xaxis)   # xaxis must be visible for grid
                 self._check_visible(ax.get_xticklabels(), visible=False)
+                self._check_visible(ax.get_xticklabels(minor=True), visible=False)
+                self._check_visible(ax.xaxis.get_label(), visible=False)
                 self._check_visible(ax.get_yticklabels())
 
+            self._check_visible(axes[-1].xaxis)
             self._check_visible(axes[-1].get_xticklabels())
+            self._check_visible(axes[-1].get_xticklabels(minor=True))
+            self._check_visible(axes[-1].xaxis.get_label())
             self._check_visible(axes[-1].get_yticklabels())
 
             axes = df.plot(kind=kind, subplots=True, sharex=False)
             for ax in axes:
+                self._check_visible(ax.xaxis)
                 self._check_visible(ax.get_xticklabels())
+                self._check_visible(ax.get_xticklabels(minor=True))
+                self._check_visible(ax.xaxis.get_label())
                 self._check_visible(ax.get_yticklabels())
 
             axes = df.plot(kind=kind, subplots=True, legend=False)
             for ax in axes:
                 self.assertTrue(ax.get_legend() is None)
 
+    @slow
+    def test_subplots_timeseries(self):
+        idx = date_range(start='2014-07-01', freq='M', periods=10)
+        df = DataFrame(np.random.rand(10, 3), index=idx)
+
+        for kind in ['line', 'area']:
+            axes = df.plot(kind=kind, subplots=True, sharex=True)
+            self._check_axes_shape(axes, axes_num=3, layout=(3, 1))
+
+            for ax in axes[:-2]:
+                # GH 7801
+                self._check_visible(ax.xaxis)   # xaxis must be visible for grid
+                self._check_visible(ax.get_xticklabels(), visible=False)
+                self._check_visible(ax.get_xticklabels(minor=True), visible=False)
+                self._check_visible(ax.xaxis.get_label(), visible=False)
+                self._check_visible(ax.get_yticklabels())
+
+            self._check_visible(axes[-1].xaxis)
+            self._check_visible(axes[-1].get_xticklabels())
+            self._check_visible(axes[-1].get_xticklabels(minor=True))
+            self._check_visible(axes[-1].xaxis.get_label())
+            self._check_visible(axes[-1].get_yticklabels())
+
+            axes = df.plot(kind=kind, subplots=True, sharex=False)
+            for ax in axes:
+                self._check_visible(ax.xaxis)
+                self._check_visible(ax.get_xticklabels())
+                self._check_visible(ax.get_xticklabels(minor=True))
+                self._check_visible(ax.xaxis.get_label())
+                self._check_visible(ax.get_yticklabels())
+
     def test_negative_log(self):
         df = - DataFrame(rand(6, 4),
                        index=list(string.ascii_letters[:6]),

pandas/tools/plotting.py

@@ -2972,16 +2972,35 @@ def _subplots(nrows=1, ncols=1, naxes=None, sharex=False, sharey=False, squeeze=
         axarr[i] = ax
 
     if nplots > 1:
+        
         if sharex and nrows > 1:
             for ax in axarr[:naxes][:-ncols]:    # only bottom row
                 for label in ax.get_xticklabels():
                     label.set_visible(False)
+                try:
+                    # set_visible will not be effective if
+                    # minor axis has NullLocator and NullFormattor (default)
+                    import matplotlib.ticker as ticker
+                    ax.xaxis.set_minor_locator(ticker.AutoLocator())
+                    ax.xaxis.set_minor_formatter(ticker.FormatStrFormatter(''))
+                    for label in ax.get_xticklabels(minor=True):
+                        label.set_visible(False)
+                except Exception:   # pragma no cover
+                    pass
                 ax.xaxis.get_label().set_visible(False)
         if sharey and ncols > 1:
             for i, ax in enumerate(axarr):
                 if (i % ncols) != 0:  # only first column
                     for label in ax.get_yticklabels():
                         label.set_visible(False)
+                    try:
+                        import matplotlib.ticker as ticker
+                        ax.yaxis.set_minor_locator(ticker.AutoLocator())
+                        ax.yaxis.set_minor_formatter(ticker.FormatStrFormatter(''))
+                        for label in ax.get_yticklabels(minor=True):
+                            label.set_visible(False)
+                    except Exception:   # pragma no cover
+                        pass
                     ax.yaxis.get_label().set_visible(False)
 
     if naxes != nplots: