torch.nn.functional.pdist

torch.nn.functional.pdist(input, p=2) → Tensor

Computes the p-norm distance between every pair of row vectors in the input. This is identical to the upper triangular portion, excluding the diagonal, of torch.norm(input[:, None] - input, dim=2, p=p). This function will be faster if the rows are contiguous.

If input has shape $N \times M$ then the output will have shape $\frac{1}{2} N (N - 1)$.

This function is equivalent to scipy.spatial.distance.pdist(input, 'minkowski', p=p) if $p \in (0, \infty)$. When $p = 0$ it is equivalent to scipy.spatial.distance.pdist(input, 'hamming') * M. When $p = \infty$, the closest scipy function is scipy.spatial.distance.pdist(xn, lambda x, y: np.abs(x - y).max()).

Parameters

• input – input tensor of shape $N \times M$.

• p – p value for the p-norm distance to calculate between each vector pair $\in [0, \infty]$.