torch.kthvalue

torch.kthvalue(input, k, dim=None, keepdim=False, *, out=None)

Returns a namedtuple (values, indices) where values is the k th smallest element of each row of the input tensor in the given dimension dim. And indices is the index location of each element found.

If dim is not given, the last dimension of the input is chosen.

If keepdim is True, both the values and indices tensors are the same size as input, except in the dimension dim where they are of size 1. Otherwise, dim is squeezed (see torch.squeeze()), resulting in both the values and indices tensors having 1 fewer dimension than the input tensor.

Note

When input is a CUDA tensor and there are multiple valid k th values, this function may nondeterministically return indices for any of them.

Parameters:

• input (Tensor) – the input tensor.

• k (int) – k for the k-th smallest element

• dim (int, optional) – the dimension to find the kth value along

• keepdim (bool) – whether the output tensor has dim retained or not.

Keyword Arguments:

out (tuple, optional) – the output tuple of (Tensor, LongTensor) can be optionally given to be used as output buffers

Example:

>>> x = torch.arange(1., 6.)
>>> x
tensor([ 1.,  2.,  3.,  4.,  5.])
>>> torch.kthvalue(x, 4)
torch.return_types.kthvalue(values=tensor(4.), indices=tensor(3))

>>> x=torch.arange(1.,7.).resize_(2,3)
>>> x
tensor([[ 1.,  2.,  3.],
        [ 4.,  5.,  6.]])
>>> torch.kthvalue(x, 2, 0, True)
torch.return_types.kthvalue(values=tensor([[4., 5., 6.]]), indices=tensor([[1, 1, 1]]))