ITensor / ITensor/ITensorMPS.jl

[ITensors] [BUG] maxlinkdim(MPS(sinds; linkdims=0)) returns 1

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bug
Dominant language
Julia
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Merged PRs (30d)
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Description

sinds = [Index(2) for _ in 1:5]
maxlinkdim(MPS(sinds; linkdims=0))   # returns 1

I realize this is a weird corner case, and the docs state that maxlinkdim() returns minimum 1, but it feels odd since once can construct such MPS. Perhaps if you really want to keep the minimum of 1, this should throw an error?

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Research direction

Reproduce the Julia example using Index, MPS, and maxlinkdim with linkdims=0, then trace the implementations of MPS construction and maxlinkdim. Check how the documented minimum of 1 is enforced and determine the expected behavior for this constructible corner case; done means the behavior is made consistent with the chosen expectation.

Written by the indexing model from the issue text.

Assessment

Tech stack
julia
Domain
hpc
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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