# pandas.MultiIndex.set_levels

MultiIndex.set_levels(levels, level=None, inplace=None, verify_integrity=True)

  Set new levels on MultiIndex. Defaults to returning new index.

  Parameters
    levels sequence or list of sequence

      New level(s) to apply.

    level int, level name, or sequence of int/level names (default None)

      Level(s) to set (None for all levels).

    inplace bool

      If True, mutates in place.

      Deprecated since version 1.2.0.

    verify_integrity bool, default True

      If True, checks that levels and codes are compatible.

  Returns
    new index (of same type and class…etc) or None

      The same type as the caller or None if `inplace=True`.

  Examples

      >>> idx = pd.MultiIndex.from_tuples(
      ...     [
      ...         (1, "one"),
      ...         (1, "two"),
      ...         (2, "one"),
      ...         (2, "two"),
      ...         (3, "one"),
      ...         (3, "two")
      ...     ],
      ...     names=["foo", "bar"]
      ... )
      >>> idx
      MultiIndex([(1, 'one'),
          (1, 'two'),
          (2, 'one'),
          (2, 'two'),
          (3, 'one'),
          (3, 'two')],
         names=['foo', 'bar'])

      >>> idx.set_levels([['a', 'b', 'c'], [1, 2]])
      MultiIndex([('a', 1),
                  ('a', 2),
                  ('b', 1),
                  ('b', 2),
                  ('c', 1),
                  ('c', 2)],
                 names=['foo', 'bar'])
      >>> idx.set_levels(['a', 'b', 'c'], level=0)
      MultiIndex([('a', 'one'),
                  ('a', 'two'),
                  ('b', 'one'),
                  ('b', 'two'),
                  ('c', 'one'),
                  ('c', 'two')],
                 names=['foo', 'bar'])
      >>> idx.set_levels(['a', 'b'], level='bar')
      MultiIndex([(1, 'a'),
                  (1, 'b'),
                  (2, 'a'),
                  (2, 'b'),
                  (3, 'a'),
                  (3, 'b')],
                 names=['foo', 'bar'])

  If any of the levels passed to `set_levels()` exceeds the existing length, all of the values from that argument will be stored in the MultiIndex levels, though the values will be truncated in the MultiIndex output.

      >>> idx.set_levels([['a', 'b', 'c'], [1, 2, 3, 4]], level=[0, 1])
      MultiIndex([('a', 1),
          ('a', 2),
          ('b', 1),
          ('b', 2),
          ('c', 1),
          ('c', 2)],
         names=['foo', 'bar'])
      >>> idx.set_levels([['a', 'b', 'c'], [1, 2, 3, 4]], level=[0, 1]).levels
      FrozenList([['a', 'b', 'c'], [1, 2, 3, 4]])