👌 use other._values instead of other.values and .to_frame().T

Author: Marco Gorelli

pandas/core/frame.py

@@ -6758,17 +6758,19 @@ def append(self, other, ignore_index=False, verify_integrity=False, sort=False):
                 )
 
             index = Index([other.name], name=self.index.name)
+
             idx_diff = other.index.difference(self.columns)
             try:
                 combined_columns = self.columns.append(idx_diff)
             except TypeError:
                 combined_columns = self.columns.astype(object).append(idx_diff)
-            other = (
-                other.reindex(combined_columns, copy=False)
-                .to_frame()
-                .T.infer_objects()
-                .rename_axis(index.names)
+            other = other.reindex(combined_columns, copy=False)
+            other = DataFrame(
+                other._values.reshape((1, len(other))),
+                index=index,
+                columns=combined_columns
             )
+            other = other.infer_objects()
             if not self.columns.equals(combined_columns):
                 self = self.reindex(columns=combined_columns)
         elif isinstance(other, list):