torch.sparse.addmm

torch.sparse.addmm(mat, mat1, mat2, *, beta=1., alpha=1.) → Tensor

This function does exact same thing as torch.addmm() in the forward, except that it supports backward for sparse COO and CSR matrix mat1. When mat1 is a COO tensor it must have sparse_dim = 2.

Supports both CSR and COO storage formats.

Note

Gradient support:

• COO @ Dense: Backward is supported for both inputs. The gradient for the sparse input is returned as a sparse COO tensor.

• CSR @ Dense: Backward is supported for both inputs. The gradient for the sparse input is returned as a sparse CSR tensor.

• CSC/BSR/BSC @ Dense: Not supported.

• Sparse @ Sparse (COO @ COO, CSR @ CSR): Forward works, but backward is not supported.

Parameters:

• mat (Tensor) – a dense matrix to be added

• mat1 (Tensor) – a sparse matrix to be multiplied

• mat2 (Tensor) – a dense matrix to be multiplied

• beta (Number, optional) – multiplier for mat ($\beta$)

• alpha (Number, optional) – multiplier for $mat1 @ mat2$ ($\alpha$)