code sample for pandas-dev#46867

Author: simonjayhawkins

bisect/46867.py

@@ -0,0 +1,18 @@
+# BUG: groupby.transform with execution engine numba does not work in multiindex case since 1.3 #46867
+
+import pandas as pd
+
+print(pd.__version__)
+
+df = pd.DataFrame([{"A": 1, "B": 2, "C": 3}]).set_index(["A", "B"])
+
+
+def numba_func(values, index):
+    return 1
+
+
+result = df.groupby("A").transform(numba_func, engine="numba")
+print(result)
+
+expected = pd.DataFrame([{"A": 1, "B": 2, "C": 1.0}]).set_index(["A", "B"])
+pd.testing.assert_frame_equal(result, expected)