outer

Return outer product of two sparse arrays.

Parameters:

Name	Type	Description	Default
a	SparseArray	The input arrays.	required
b	SparseArray	The input arrays.	required
out	SparseArray	The output array.	None

Examples:

>>> import numpy as np
>>> import sparse
>>> a = sparse.COO(np.arange(4))
>>> o = sparse.outer(a, a)
>>> o.todense()
array([[0, 0, 0, 0],
       [0, 1, 2, 3],
       [0, 2, 4, 6],
       [0, 3, 6, 9]])

Source code in sparse/numba_backend/_common.py

def outer(a, b, out=None):
    """
    Return outer product of two sparse arrays.

    Parameters
    ----------
    a, b : sparse.SparseArray
        The input arrays.
    out : sparse.SparseArray
        The output array.

    Examples
    --------
    >>> import numpy as np
    >>> import sparse
    >>> a = sparse.COO(np.arange(4))
    >>> o = sparse.outer(a, a)
    >>> o.todense()
    array([[0, 0, 0, 0],
           [0, 1, 2, 3],
           [0, 2, 4, 6],
           [0, 3, 6, 9]])
    """
    from ._coo import COO
    from ._sparse_array import SparseArray

    if isinstance(a, SparseArray):
        a = COO(a)
    if isinstance(b, SparseArray):
        b = COO(b)
    return np.multiply.outer(a.flatten(), b.flatten(), out=out)