qfeval_functions.functions.msum

msum(x, span, dim=-1)

Compute the moving (sliding window) sum of a tensor.

This function calculates the sum of elements within a sliding window of size span along the specified dimension. The output tensor has the same shape as the input tensor. For positions where the sliding window cannot fully cover preceding elements (i.e., the first span - 1 elements along the selected dimension), the result is nan.

Parameters:

• x (Tensor) – The input tensor.

• span (int) – The size of the sliding window.

• dim (int) – The dimension along which to compute the moving sum. Default is -1 (the last dimension).

Returns:

A tensor of the same shape as the input, containing the moving sums.

Return type:

Tensor

Example

>>> x = torch.tensor([1.0, 2.0, 3.0, 4.0, 5.0])
>>> QF.msum(x, span=3)
tensor([nan, nan,  6.,  9., 12.])

>>> x = torch.tensor([[1.0, 2.0, 3.0, 4.0],
...                   [5.0, 6.0, 7.0, 8.0]])
>>> QF.msum(x, span=2, dim=1)
tensor([[nan,  3.,  5.,  7.],
        [nan, 11., 13., 15.]])