pandas.DataFrame.xs — pandas 3.0.0.dev0+2098.g9c5b9ee823 documentation (original) (raw)

DataFrame.xs(key, axis=0, level=None, drop_level=True)[source]#

Return cross-section from the Series/DataFrame.

This method takes a key argument to select data at a particular level of a MultiIndex.

Parameters:

keylabel or tuple of label

Label contained in the index, or partially in a MultiIndex.

axis{0 or ‘index’, 1 or ‘columns’}, default 0

Axis to retrieve cross-section on.

levelobject, defaults to first n levels (n=1 or len(key))

In case of a key partially contained in a MultiIndex, indicate which levels are used. Levels can be referred by label or position.

drop_levelbool, default True

If False, returns object with same levels as self.

Returns:

Series or DataFrame

Cross-section from the original Series or DataFrame corresponding to the selected index levels.

See also

DataFrame.loc

Access a group of rows and columns by label(s) or a boolean array.

DataFrame.iloc

Purely integer-location based indexing for selection by position.

Notes

xs can not be used to set values.

MultiIndex Slicers is a generic way to get/set values on any level or levels. It is a superset of xs functionality, seeMultiIndex Slicers.

Examples

d = { ... "num_legs": [4, 4, 2, 2], ... "num_wings": [0, 0, 2, 2], ... "class": ["mammal", "mammal", "mammal", "bird"], ... "animal": ["cat", "dog", "bat", "penguin"], ... "locomotion": ["walks", "walks", "flies", "walks"], ... } df = pd.DataFrame(data=d) df = df.set_index(["class", "animal", "locomotion"]) df num_legs num_wings class animal locomotion mammal cat walks 4 0 dog walks 4 0 bat flies 2 2 bird penguin walks 2 2

Get values at specified index

df.xs("mammal") num_legs num_wings animal locomotion cat walks 4 0 dog walks 4 0 bat flies 2 2

Get values at several indexes

df.xs(("mammal", "dog", "walks")) num_legs 4 num_wings 0 Name: (mammal, dog, walks), dtype: int64

Get values at specified index and level

df.xs("cat", level=1) num_legs num_wings class locomotion mammal walks 4 0

Get values at several indexes and levels

df.xs(("bird", "walks"), level=[0, "locomotion"]) num_legs num_wings animal penguin 2 2

Get values at specified column and axis

df.xs("num_wings", axis=1) class animal locomotion mammal cat walks 0 dog walks 0 bat flies 2 bird penguin walks 2 Name: num_wings, dtype: int64