Hi, I used pytorch 1.1 and I have a question about making mask tensor using index tensor.
I have a simple example for understanding.
For example, I have index tensor (size is [2, 4]) which is look like below:
tensor([[0, 0, 2, 4], [0, 0, 0, 3]])
and finally, I want to get mask tensor (size is [2, 4, 6]) like this:
tensor([[[1., 0., 0., 0., 0., 0.],
 [1., 0., 0., 0., 0., 0.],
 [0., 0., 1., 0., 0., 0.],
[0., 0., 0., 0., 1., 0.]],
[[1., 0., 0., 0., 0., 0.],
[1., 0., 0., 0., 0., 0.],
[1., 0., 0., 0., 0., 0.],
[0., 0., 0., 1., 0., 0.]]])
I implemented it using a for loop statement twice like below, but if the tensor size is large (for example, mask size is [32, 8732, 21]), it is too slow to use for training.

Blockquote
for i in range(mask.size(0)):
for j in range(mask.size(1)):
mask[i,j,b[i,j]] = 1

Is there any way to implement the action quickly without using the for loop?
Thank you in advance.