Question about calculating IoU.

[SkyeFromKindergarten]

Thanks for your great work at first~

You calculated IoU of voxels in core/test.py line129-134. I have some questions about that.

Line 133: union = torch.sum(torch.ge(_volume.add(ground_truth_volume), 1)).float()
I think a union includes 3 parts:

1. volume = 1 and gt = 1 => 1+1=2
2. volume = 0 and gt = 1 => 0+1=1
3. volume = 1 and gt = 0 => 1+0=1

But I find that in your code, it only includes 2) and 3). Because you throw away the voxel-pair, whose sum is 2, by torch.ge(add_reslut,1).
Am I wrong somewhere? Looking for reply.

Best regards.

[hzxie]

I don't think there's anything wrong with this code.
The following code

_volume = torch.ge(generated_volume, th).float()
union = torch.sum(torch.ge(_volume.add(ground_truth_volume), 1)).float()

is equivalent to

_volume = _volume >= th
_volume = _volume + ground_truth_volume
_volume = _volume >= 1
union = torch.sum(_volume).float()

If you cannot understand the code above, you can implement it by yourself. And you will find that the results are the same.

[SkyeFromKindergarten]

Ok thanks a lot ! I got mess with torch.ge(), thanks for your patient explanation !