xarray.Dataset.to_stacked_array

Dataset.to_stacked_array(new_dim, sample_dims, variable_dim='variable', name=None)

Combine variables of differing dimensionality into a DataArray without broadcasting.

This method is similar to Dataset.to_array but does not broadcast the variables.

Parameters

new_dimstr

Name of the new stacked coordinate

sample_dimsSequence[str]

Dimensions that will not be stacked. Each array in the dataset must share these dimensions. For machine learning applications, these define the dimensions over which samples are drawn.

variable_dimstr, optional

Name of the level in the stacked coordinate which corresponds to the variables.

namestr, optional

Name of the new data array.

Returns

stackedDataArray

DataArray with the specified dimensions and data variables stacked together. The stacked coordinate is named new_dim and represented by a MultiIndex object with a level containing the data variable names. The name of this level is controlled using the variable_dim argument.

See also

Dataset.to_array, Dataset.stack, DataArray.to_unstacked_dataset

Examples

>>> data = Dataset(
...     data_vars={'a': (('x', 'y'), [[0, 1, 2], [3, 4, 5]]),
...                'b': ('x', [6, 7])},
...     coords={'y': ['u', 'v', 'w']}
... )

>>> data
<xarray.Dataset>
Dimensions:  (x: 2, y: 3)
Coordinates:
* y        (y) <U1 'u' 'v' 'w'
Dimensions without coordinates: x
Data variables:
    a        (x, y) int64 0 1 2 3 4 5
    b        (x) int64 6 7

>>> data.to_stacked_array("z", sample_dims=['x'])
<xarray.DataArray (x: 2, z: 4)>
array([[0, 1, 2, 6],
    [3, 4, 5, 7]])
Coordinates:
* z         (z) MultiIndex
- variable  (z) object 'a' 'a' 'a' 'b'
- y         (z) object 'u' 'v' 'w' nan
Dimensions without coordinates: x