xarray.Dataset.set_index#
- Dataset.set_index(indexes=None, append=False, **indexes_kwargs)[source]#
Set Dataset (multi-)indexes using one or more existing coordinates or variables.
This legacy method is limited to pandas (multi-)indexes and 1-dimensional “dimension” coordinates. See
set_xindex()
for setting a pandas or a custom Xarray-compatible index from one or more arbitrary coordinates.- Parameters
indexes (
{dim: index, ...}
) – Mapping from names matching dimensions and values given by (lists of) the names of existing coordinates or variables to set as new (multi-)index.append (
bool
, default:False
) – If True, append the supplied index(es) to the existing index(es). Otherwise replace the existing index(es) (default).**indexes_kwargs (optional) – The keyword arguments form of
indexes
. One of indexes or indexes_kwargs must be provided.
- Returns
obj (
Dataset
) – Another dataset, with this dataset’s data but replaced coordinates.
Examples
>>> arr = xr.DataArray( ... data=np.ones((2, 3)), ... dims=["x", "y"], ... coords={"x": range(2), "y": range(3), "a": ("x", [3, 4])}, ... ) >>> ds = xr.Dataset({"v": arr}) >>> ds <xarray.Dataset> Size: 104B Dimensions: (x: 2, y: 3) Coordinates: * x (x) int64 16B 0 1 * y (y) int64 24B 0 1 2 a (x) int64 16B 3 4 Data variables: v (x, y) float64 48B 1.0 1.0 1.0 1.0 1.0 1.0 >>> ds.set_index(x="a") <xarray.Dataset> Size: 88B Dimensions: (x: 2, y: 3) Coordinates: * x (x) int64 16B 3 4 * y (y) int64 24B 0 1 2 Data variables: v (x, y) float64 48B 1.0 1.0 1.0 1.0 1.0 1.0