入会申込
ログインfrom pandas.api.types import CategoricalDtypedf = pd.DataFrame({"A": np.arange(6), "B": list("aabbca")})df["B"] = df["B"].astype(CategoricalDtype(list("cab")))df["B"].cat.categoriesdf2 = df.set_index("B")df2.loc["a"]df2.loc["a"].indexdf2.sort_index()df2.groupby(level=0).sum()df2.groupby(level=0).sum().indexdf3 = pd.DataFrame({"A": np.arange(3), "B": pd.Series(list("abc")).astype("category")})df3 = df3.set_index("B")df3.reindex(["a", "e"])df3.reindex(["a", "e"]).indexdf3.reindex(pd.Categorical(["a", "e"], categories=list("abe")))df3.reindex(pd.Categorical(["a", "e"], categories=list("abe"))).index
