DataFrame.
sort_index
Sort object by labels (along an axis).
Returns a new DataFrame sorted by label if inplace argument is False, otherwise updates the original DataFrame and returns None.
False
The axis along which to sort. The value 0 identifies the rows, and 1 identifies the columns.
If not None, sort on values in specified index level(s).
Sort ascending vs. descending. When the index is a MultiIndex the sort direction can be controlled for each level individually.
If True, perform operation in-place.
Choice of sorting algorithm. See also ndarray.np.sort for more information. mergesort is the only stable algorithm. For DataFrames, this option is only applied when sorting on a single column or label.
Puts NaNs at the beginning if first; last puts NaNs at the end. Not implemented for MultiIndex.
If True and sorting by level and index is multilevel, sort by other levels too (in order) after sorting by specified level.
If True, the resulting axis will be labeled 0, 1, …, n - 1.
New in version 1.0.0.
If not None, apply the key function to the index values before sorting. This is similar to the key argument in the builtin sorted() function, with the notable difference that this key function should be vectorized. It should expect an Index and return an Index of the same shape. For MultiIndex inputs, the key is applied per level.
sorted()
Index
New in version 1.1.0.
The original DataFrame sorted by the labels.
See also
Series.sort_index
Sort Series by the index.
DataFrame.sort_values
Sort DataFrame by the value.
Series.sort_values
Sort Series by the value.
Examples
>>> df = pd.DataFrame([1, 2, 3, 4, 5], index=[100, 29, 234, 1, 150], ... columns=['A']) >>> df.sort_index() A 1 4 29 2 100 1 150 5 234 3
By default, it sorts in ascending order, to sort in descending order, use ascending=False
ascending=False
>>> df.sort_index(ascending=False) A 234 3 150 5 100 1 29 2 1 4
A key function can be specified which is applied to the index before sorting. For a MultiIndex this is applied to each level separately.
MultiIndex
>>> df = pd.DataFrame({"a": [1, 2, 3, 4]}, index=['A', 'b', 'C', 'd']) >>> df.sort_index(key=lambda x: x.str.lower()) a A 1 b 2 C 3 d 4