I want to make the value of a specific index equal to 0. but very very slow…

```
mask = [1,2,3,4]
input = torch.zeros(100,64,32,32)
for m in mask:
for i in range(100):
input[i][m] = 0
```

How do I optimize my code?

I want to make the value of a specific index equal to 0. but very very slow…

```
mask = [1,2,3,4]
input = torch.zeros(100,64,32,32)
for m in mask:
for i in range(100):
input[i][m] = 0
```

How do I optimize my code?

This code should work:

```
x = torch.zeros(100, 64, 32, 32)
mask = torch.tensor([1,2,3,4])
x[:, mask] = 1
```

Note that I changed the assignment to a 1, otherwise you would reassign a 0 to the tensor containing all zeros.

1 Like

Good JOB!! Many Thanks!!!

How to do this in the last dimension of the tensor?