Solved by googlebot in post #8 
              
              
                well, let’s see… 
you want to compact a dimension in the middle, I’ll simplify this to dims representing (B*C,T,H*W) and sizes 2,4,3 

x = torch.zeros(2,4,3) 
x[:,::2].copy_(torch.arange(12).view(2,2,3)) #values we want to extract 
y = x.view(2*4,3)[:4] #compact and truncated area to copy into 
y.co…