dask.array.concatenate

dask.array.concatenate

dask.array.concatenate(seq, axis=0, allow_unknown_chunksizes=False)[source]

Concatenate arrays along an existing axis

Given a sequence of dask Arrays form a new dask Array by stacking them along an existing dimension (axis=0 by default)

Parameters
seq: list of dask.arrays
axis: int

Dimension along which to align all of the arrays. If axis is None, arrays are flattened before use.

allow_unknown_chunksizes: bool

Allow unknown chunksizes, such as come from converting from dask dataframes. Dask.array is unable to verify that chunks line up. If data comes from differently aligned sources then this can cause unexpected results.

See also

stack

Examples

Create slices

>>> import dask.array as da
>>> import numpy as np
>>> data = [da.from_array(np.ones((4, 4)), chunks=(2, 2))
...          for i in range(3)]
>>> x = da.concatenate(data, axis=0)
>>> x.shape
(12, 4)
>>> da.concatenate(data, axis=1).shape
(4, 12)

Result is a new dask Array