BUG: fix custom xticks in bar() plotting function (pandas-dev#28172)

* Fixing issue pandas-dev#14119

Author: GiuPassarelli

doc/source/whatsnew/v1.0.0.rst

@@ -263,6 +263,7 @@ Plotting
 - Bug in :meth:`DataFrame.plot` when ``kind='box'`` and data contains datetime or timedelta data. These types are now automatically dropped (:issue:`22799`)
 - Bug in :meth:`DataFrame.plot.line` and :meth:`DataFrame.plot.area` produce wrong xlim in x-axis (:issue:`27686`, :issue:`25160`, :issue:`24784`)
 - Bug where :meth:`DataFrame.boxplot` would not accept a `color` parameter like `DataFrame.plot.box` (:issue:`26214`)
+- Bug in the ``xticks`` argument being ignored for :meth:`DataFrame.plot.bar` (:issue:`14119`)
 - :func:`set_option` now validates that the plot backend provided to ``'plotting.backend'`` implements the backend when the option is set, rather than when a plot is created (:issue:`28163`)
 
 Groupby/resample/rolling

pandas/plotting/_matplotlib/core.py

@@ -1435,8 +1435,13 @@ def _post_plot_logic(self, ax, data):
 
     def _decorate_ticks(self, ax, name, ticklabels, start_edge, end_edge):
         ax.set_xlim((start_edge, end_edge))
-        ax.set_xticks(self.tick_pos)
-        ax.set_xticklabels(ticklabels)
+
+        if self.xticks is not None:
+            ax.set_xticks(np.array(self.xticks))
+        else:
+            ax.set_xticks(self.tick_pos)
+            ax.set_xticklabels(ticklabels)
+
         if name is not None and self.use_index:
             ax.set_xlabel(name)
 

pandas/tests/plotting/test_series.py

@@ -871,6 +871,13 @@ def test_xticklabels(self):
         exp = ["P{i:02d}".format(i=i) for i in [0, 3, 5, 9]]
         self._check_text_labels(ax.get_xticklabels(), exp)
 
+    def test_xtick_barPlot(self):
+        # GH28172
+        s = pd.Series(range(10), index=["P{i:02d}".format(i=i) for i in range(10)])
+        ax = s.plot.bar(xticks=range(0, 11, 2))
+        exp = np.array(list(range(0, 11, 2)))
+        tm.assert_numpy_array_equal(exp, ax.get_xticks())
+
     def test_custom_business_day_freq(self):
         # GH7222
         from pandas.tseries.offsets import CustomBusinessDay