BUG: Fixes plotting with nullable integers (#32073) (#38014)

Author: rkc007

doc/source/whatsnew/v1.2.0.rst

@@ -746,6 +746,7 @@ Plotting
  indexed by a :class:`.TimedeltaIndex` with a fixed frequency and the x-axis lower limit was greater than the upper limit (:issue:`37454`)
 - Bug in :meth:`.DataFrameGroupBy.boxplot` when ``subplots=False`` would raise a ``KeyError`` (:issue:`16748`)
 - Bug in :meth:`DataFrame.plot` and :meth:`Series.plot` was overwriting matplotlib's shared y axes behaviour when no ``sharey`` parameter was passed (:issue:`37942`)
+- Bug in :meth:`DataFrame.plot` was raising a ``TypeError`` with ``ExtensionDtype`` columns (:issue:`32073`)
 
 
 Groupby/resample/rolling

pandas/plotting/_matplotlib/core.py

@@ -9,9 +9,12 @@
 from pandas.util._decorators import cache_readonly
 
 from pandas.core.dtypes.common import (
+ is_extension_array_dtype,
  is_float,
+ is_float_dtype,
  is_hashable,
  is_integer,
+ is_integer_dtype,
  is_iterator,
  is_list_like,
  is_number,
@@ -383,6 +386,20 @@ def result(self):
  else:
  return self.axes[0]
 
+ def _convert_to_ndarray(self, data):
+ # GH32073: cast to float if values contain nulled integers
+ if (
+ is_integer_dtype(data.dtype) or is_float_dtype(data.dtype)
+ ) and is_extension_array_dtype(data.dtype):
+ return data.to_numpy(dtype="float", na_value=np.nan)
+
+ # GH25587: cast ExtensionArray of pandas (IntegerArray, etc.) to
+ # np.ndarray before plot.
+ if len(data) > 0:
+ return np.asarray(data)
+
+ return data
+
  def _compute_plot_data(self):
  data = self.data
 
@@ -423,13 +440,7 @@ def _compute_plot_data(self):
  if is_empty:
  raise TypeError("no numeric data to plot")
 
- # GH25587: cast ExtensionArray of pandas (IntegerArray, etc.) to
- # np.ndarray before plot.
- numeric_data = numeric_data.copy()
- for col in numeric_data:
- numeric_data[col] = np.asarray(numeric_data[col])
-
- self.data = numeric_data
+ self.data = numeric_data.apply(self._convert_to_ndarray)
 
  def _make_plot(self):
  raise AbstractMethodError(self)

pandas/tests/plotting/frame/test_frame.py

@@ -149,6 +149,28 @@ def test_plot(self):
  result = ax.axes
  assert result is axes[0]
 
+ def test_nullable_int_plot(self):
+ # GH 32073
+ dates = ["2008", "2009", None, "2011", "2012"]
+ df = DataFrame(
+ {
+ "A": [1, 2, 3, 4, 5],
+ "B": [1.0, 2.0, 3.0, 4.0, 5.0],
+ "C": [7, 5, np.nan, 3, 2],
+ "D": pd.to_datetime(dates, format="%Y"),
+ "E": pd.to_datetime(dates, format="%Y", utc=True),
+ },
+ dtype=np.int64,
+ )
+
+ _check_plot_works(df.plot, x="A", y="B")
+ _check_plot_works(df[["A", "B"]].plot, x="A", y="B")
+ _check_plot_works(df[["C", "A"]].plot, x="C", y="A") # nullable value on x-axis
+ _check_plot_works(df[["A", "C"]].plot, x="A", y="C")
+ _check_plot_works(df[["B", "C"]].plot, x="B", y="C")
+ _check_plot_works(df[["A", "D"]].plot, x="A", y="D")
+ _check_plot_works(df[["A", "E"]].plot, x="A", y="E")
+
  def test_integer_array_plot(self):
  # GH 25587
  arr = integer_array([1, 2, 3, 4], dtype="UInt32")