Fix styling of DataFrame for columns with boolean label

doc/source/whatsnew/v1.5.0.rst

@@ -1042,6 +1042,7 @@ Styler
 - Bug in :meth:`Styler.set_sticky` leading to white text on white background in dark mode (:issue:`46984`)
 - Bug in :meth:`Styler.to_latex` causing ``UnboundLocalError`` when ``clines="all;data"`` and the ``DataFrame`` has no rows. (:issue:`47203`)
 - Bug in :meth:`Styler.to_excel` when using ``vertical-align: middle;`` with ``xlsxwriter`` engine (:issue:`30107`)
+- Bug when applying styles to a DataFrame with boolean column labels (:issue:`47838`)
 
 Metadata
 ^^^^^^^^

pandas/io/formats/style.py

@@ -2977,6 +2977,12 @@ def hide(
     # A collection of "builtin" styles
     # -----------------------------------------------------------------------
 
+    def _get_numeric_subset_default(self):
+        # Returns a boolean mask indicating where `self.data` has numerical columns.
+        # Choosing a mask as opposed to the column names also works for
+        # boolean column labels (GH47838).
+        return self.data.columns.isin(self.data.select_dtypes(include=np.number))
+
     @doc(
         name="background",
         alt="text",
@@ -3120,7 +3126,7 @@ def background_gradient(
         .. figure:: ../../_static/style/{image_prefix}_axNone_gmap.png
         """
         if subset is None and gmap is None:
-            subset = self.data.select_dtypes(include=np.number).columns
+            subset = self._get_numeric_subset_default()
 
         self.apply(
             _background_gradient,
@@ -3155,7 +3161,7 @@ def text_gradient(
         gmap: Sequence | None = None,
     ) -> Styler:
         if subset is None and gmap is None:
-            subset = self.data.select_dtypes(include=np.number).columns
+            subset = self._get_numeric_subset_default()
 
         return self.apply(
             _background_gradient,
@@ -3308,7 +3314,7 @@ def bar(
             raise ValueError(f"`height` must be a value in [0, 100], got {height}")
 
         if subset is None:
-            subset = self.data.select_dtypes(include=np.number).columns
+            subset = self._get_numeric_subset_default()
 
         self.apply(
             _bar,

pandas/tests/io/formats/style/test_style.py

@@ -746,6 +746,22 @@ def color_negative_red(val):
         df.loc[pct_subset]
         df.style.applymap(color_negative_red, subset=pct_subset)
 
+    @pytest.mark.parametrize(
+        "stylefunc", ["background_gradient", "bar", "text_gradient"]
+    )
+    def test_subset_for_boolean_cols(self, stylefunc):
+        # GH47838
+        df = DataFrame(
+            [
+                [1, 2],
+                [3, 4],
+            ],
+            columns=[False, True],
+        )
+        styled = getattr(df.style, stylefunc)()
+        styled._compute()
+        assert set(styled.ctx) == {(0, 0), (0, 1), (1, 0), (1, 1)}
+
     def test_empty(self):
         df = DataFrame({"A": [1, 0]})
         s = df.style