PLT: Order of plots does not preserve the column orders in df.hist (#33336)

Author: charlesdong1991

doc/source/whatsnew/v1.1.0.rst

@@ -703,6 +703,7 @@ Plotting
 - :func:`.plot` for line/bar now accepts color by dictonary (:issue:`8193`).
 - Bug in :meth:`DataFrame.plot.hist` where weights are not working for multiple columns (:issue:`33173`)
 - Bug in :meth:`DataFrame.boxplot` and :meth:`DataFrame.plot.boxplot` lost color attributes of ``medianprops``, ``whiskerprops``, ``capprops`` and ``medianprops`` (:issue:`30346`)
+- Bug in :meth:`DataFrame.hist` where the order of ``column`` argument was ignored (:issue:`29235`)
 - Bug in :meth:`DataFrame.plot.scatter` that when adding multiple plots with different ``cmap``, colorbars alway use the first ``cmap`` (:issue:`33389`)
 
 

pandas/plotting/_matplotlib/hist.py

@@ -4,8 +4,6 @@
 from pandas.core.dtypes.generic import ABCDataFrame, ABCIndexClass
 from pandas.core.dtypes.missing import isna, remove_na_arraylike
 
-import pandas.core.common as com
-
 from pandas.io.formats.printing import pprint_thing
 from pandas.plotting._matplotlib.core import LinePlot, MPLPlot
 from pandas.plotting._matplotlib.tools import _flatten, _set_ticks_props, _subplots
@@ -403,7 +401,7 @@ def hist_frame(
     )
     _axes = _flatten(axes)
 
-    for i, col in enumerate(com.try_sort(data.columns)):
+    for i, col in enumerate(data.columns):
         ax = _axes[i]
         ax.hist(data[col].dropna().values, bins=bins, **kwds)
         ax.set_title(col)

pandas/tests/plotting/test_hist_method.py

@@ -269,6 +269,30 @@ def test_hist_subplot_xrot(self):
         )
         self._check_ticks_props(axes, xrot=0)
 
+    @pytest.mark.parametrize(
+        "column, expected",
+        [
+            (None, ["width", "length", "height"]),
+            (["length", "width", "height"], ["length", "width", "height"]),
+        ],
+    )
+    def test_hist_column_order_unchanged(self, column, expected):
+        # GH29235
+
+        df = DataFrame(
+            {
+                "width": [0.7, 0.2, 0.15, 0.2, 1.1],
+                "length": [1.5, 0.5, 1.2, 0.9, 3],
+                "height": [3, 0.5, 3.4, 2, 1],
+            },
+            index=["pig", "rabbit", "duck", "chicken", "horse"],
+        )
+
+        axes = _check_plot_works(df.hist, column=column, layout=(1, 3))
+        result = [axes[0, i].get_title() for i in range(3)]
+
+        assert result == expected
+
 
 @td.skip_if_no_mpl
 class TestDataFrameGroupByPlots(TestPlotBase):