Copy the df and transform all columns to np.array.

Signed-off-by: HE, Tao <[email protected]>

Author: sighingnow

pandas/plotting/_core.py

@@ -368,11 +368,11 @@ def _compute_plot_data(self):
 
         # GH25587: cast ExtensionArray of pandas (IntegerArray, etc.) to
         # np.ndarray before plot.
+        numeric_data_np = numeric_data.copy()
         for col in numeric_data:
-            if is_extension_array_dtype(numeric_data[col]):
-                numeric_data[col] = np.asarray(numeric_data[col])
+            numeric_data_np[col] = np.asarray(numeric_data[col])
 
-        self.data = numeric_data
+        self.data = numeric_data_np
 
     def _make_plot(self):
         raise AbstractMethodError(self)