Source code for mars.tensor.merge.union1d

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#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
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[docs]def union1d(ar1, ar2, aggregate_size=None):
"""
Find the union of two tensors.

Return the unique, sorted tensor of values that are in either of the two
input tensors.

Parameters
----------
ar1, ar2 : array_like
Input tensors. They are flattened if they are not already 1D.

Returns
-------
union1d : Tensor
Unique, sorted union of the input tensors.

Examples
--------
>>> import mars.tensor as mt

>>> mt.union1d([-1, 0, 1], [-2, 0, 2]).execute()
array([-2, -1,  0,  1,  2])

To find the union of more than two arrays, use functools.reduce:

>>> from functools import reduce
>>> reduce(mt.union1d, ([1, 3, 4, 3], [3, 1, 2, 1], [6, 3, 4, 2])).execute()
array([1, 2, 3, 4, 6])
"""

from ..base import unique, sort
from .concatenate import concatenate

result = unique(concatenate((ar1, ar2), axis=None), aggregate_size=aggregate_size)
if aggregate_size == 1:
return result
# make sure the result is sorted
# TODO(xuye.qin): remove when `mt.unique` supports sort shuffle
return sort(result)
```