Matt Fishman

It's a good question about which one to use, and each has tradeoffs. The main tradeoff of using `SmallString` is the limited tag length. I don't see why it would...

`SmallString` actually uses whatever comparison is used for `SVector`s (https://github.com/ITensor/ITensors.jl/blob/master/src/smallstring.jl#L97) which may just be a generic `AbstractArray` comparison. The `TagSet`/`SmallString` design is a bit of a mess right now, and...

Looks good, thanks @corbett5. Could you add a test for the new functionality? Also could you add something about `truncate_kwargs` in the docstring?

@corbett5 it looks like JuliaFormatter.jl v2 either accidentally or deliberately changed certain formatting rules, including introducing some bugs into the code by erroneously changing positional arguments to keyword arguments. Please...

See: https://github.com/domluna/JuliaFormatter.jl/pull/870 https://github.com/domluna/JuliaFormatter.jl/issues/878 https://github.com/domluna/JuliaFormatter.jl/issues/879 https://github.com/domluna/JuliaFormatter.jl/issues/880

I actually didn't do anything, it looks like the JuliaFormatter.jl v2 release was reverted ("yanked" in the Julia registry parlance) because there were too many bugs (https://github.com/domluna/JuliaFormatter.jl/issues/878).

@corbett5 could you move this PR over to: https://github.com/ITensor/ITensorMPS.jl?

I'll close this since it needs to be moved to the ITensorMPS.jl repository.

@jishnub I just came across a need for this, can this be merged?

> Because of how `LinearAlgebra` defines the `SVD` struct, `U` and `Vt` must have the same structure. In particular, this means that the original block matrix should have the same...