torch.Tensor.masked_scatter_ — PyTorch 2.7 documentation (original) (raw)

Tensor.masked_scatter_(mask, source)¶

Copies elements from source into self tensor at positions where the mask is True. Elements from source are copied into selfstarting at position 0 of source and continuing in order one-by-one for each occurrence of mask being True. The shape of mask must be broadcastablewith the shape of the underlying tensor. The source should have at least as many elements as the number of ones in mask.

Parameters

• mask (BoolTensor) – the boolean mask
• source (Tensor) – the tensor to copy from

Note

The mask operates on the self tensor, not on the givensource tensor.

Example

self = torch.tensor([[0, 0, 0, 0, 0], [0, 0, 0, 0, 0]]) mask = torch.tensor([[0, 0, 0, 1, 1], [1, 1, 0, 1, 1]], dtype=torch.bool) source = torch.tensor([[0, 1, 2, 3, 4], [5, 6, 7, 8, 9]]) self.masked_scatter_(mask, source) tensor([[0, 0, 0, 0, 1], [2, 3, 0, 4, 5]])