Method f

pandas/tests/frame/methods/test_reindex.py:405–406

(val)

        icol = ["jim", "joe", "jolie"]

        def f(val):
            return np.nonzero((df["jim"] == val).to_numpy())[0]

        i = np.concatenate(list(map(f, idx)))
        left = df.set_index(icol).reindex(idx, level="jim")