Olek

I updated the link to the paper

This does happen from time to time, but I think more an ANL side issue than anything to do with OpenMC.

This PR isn't quite ready yet, but it's getting there. I still need to do a bunch of testing though. Unfortunately, I'm running into a compiler error locally: ``` [...

Took another look at this today and realized that `float` is indeed not a defined type. There was one variable I added in `lattice.h` that used this type.

I have started to write a regression test. Right now the test is failing due to hitting the maximum number of lost particles due to many of the them having...

I've done some pretty in depth debugging and everything seems to be working fine until we actually cross a lattice boundary for the first time. Something is going wrong in...

I'm working on a regression test for nonuniform stack lattices. It's more or less a copy of the one for uniform stack lattices, but with the nonuniform bits added in....

`layer_boundaries_` for uniform stack lattice with 2 elements of pitch = 1.5: ``` (gdb) p layer_boundaries_ $1 = std::vector of length 3, capacity 4 = {0, 1.5, 3} ``` `layer_boundaries_`...

I did some more poking around today and realized that the `get_local_position` function doesn't handle cases where the lattice index is invalid, which I speculate is a component of telling...

This is a pretty big PR so I think 2 or 3 reviewers would be ideal @paulromano @pshriwise @anyone else who wants to review