pandas.Series.swaplevel#

Series.swaplevel(i=-2,j=-1,copy=None)[source]#

Swap levels i and j in aMultiIndex.

Default is to swap the two innermost levels of the index.

Parameters:

i, jint or str

Levels of the indices to be swapped. Can pass level name as string.

copybool, default True

Whether to copy underlying data.

Note

Thecopy keyword will change behavior in pandas 3.0.Copy-on-Writewill be enabled by default, which means that all methods with acopy keyword will use a lazy copy mechanism to defer the copy andignore thecopy keyword. Thecopy keyword will be removed in afuture version of pandas.

You can already get the future behavior and improvements throughenabling copy on writepd.options.mode.copy_on_write=True

Returns:

Series

Series with levels swapped in MultiIndex.

Examples

>>>s=pd.Series(...["A","B","A","C"],...index=[...["Final exam","Final exam","Coursework","Coursework"],...["History","Geography","History","Geography"],...["January","February","March","April"],...],...)>>>sFinal exam  History     January      A            Geography   February     BCoursework  History     March        A            Geography   April        Cdtype: object

In the following example, we will swap the levels of the indices.Here, we will swap the levels column-wise, but levels can be swapped row-wisein a similar manner. Note that column-wise is the default behaviour.By not supplying any arguments for i and j, we swap the last and second tolast indices.

>>>s.swaplevel()Final exam  January     History         A            February    Geography       BCoursework  March       History         A            April       Geography       Cdtype: object

By supplying one argument, we can choose which index to swap the lastindex with. We can for example swap the first index with the last one asfollows.

>>>s.swaplevel(0)January     History     Final exam      AFebruary    Geography   Final exam      BMarch       History     Coursework      AApril       Geography   Coursework      Cdtype: object

We can also define explicitly which indices we want to swap by supplying valuesfor both i and j. Here, we for example swap the first and second indices.

>>>s.swaplevel(0,1)History     Final exam  January         AGeography   Final exam  February        BHistory     Coursework  March           AGeography   Coursework  April           Cdtype: object