+2 votes
asked by (190 points)

Dear ITensors Team ,
I follow the the "code formula" in https://itensor.github.io/ITensors.jl/stable/Multithreading.html
Everything works well in my 0.1.41 Julia Itensor. However, a bug was reprted after updating the Julia Itensor from 0.1.41 to 0.2.6, I also try downgrading to the version 0.2.0, the same bug appears.
To be more specific, we start julia via julia -t N with N>1, code will be stopped at H = MPO(ampo, sites)
And the bug messages read

ERROR: LoadError: TaskFailedException

nested task error: UndefVarError: block1 not defined
 [1] macro expansion
   @ C:\Users\Xin-Chi Zhou\.julia\packages\ITensors\XnM47\src\NDTensors\blocksparse\blocksparsetensor.jl:1035 [inlined]
 [2] (::ITensors.NDTensors.var"#150#151"{Float64, Tuple{Int64, Int64}, Tuple{Int64, Int64}, Tuple{Int64, Int64}, Tuple{Index{Vector{Pair{QN, Int64}}}, Index{Vector{Pair{QN, Int64}}}}, Tuple{Index{Vector{Pair{QN, Int64}}}, Index{Vector{Pair{QN, Int64}}}}, Tuple{Index{Vector{Pair{QN, Int64}}}, Index{Vector{Pair{QN, Int64}}}}, Vector{Tuple{ITensors.NDTensors.Tensor, ITensors.NDTensors.Tensor, ITensors.NDTensors.Tensor}}, SubArray{UnitRange{Int64}, 1, Vector{UnitRange{Int64}}, Tuple{UnitRange{Int64}}, true}})()
   @ ITensors.NDTensors .\threadingconstructs.jl:169

The minimal code is the following:


Nx = 4
Ny = 4
N = Nx * Ny
Npart = Int(Nx * Ny / 2)
t = 1.0
D = 80

Nsweep = 2
sweeps = Sweeps(Nsweep)
maxdim!(sweeps, D)
cutoff!(sweeps, 1E-10)

sites = siteinds("Electron", N; conserve_qns=true)
lattice = square_lattice(Nx, Ny; yperiodic=true)

ampo = AutoMPO()
for b in lattice
    ampo .+= -t, "Cdagup", b.s1, "Cup", b.s2
    ampo .+= -t, "Cdagup", b.s2, "Cup", b.s1
    ampo .+= -t, "Cdagdn", b.s1, "Cdn", b.s2
    ampo .+= -t, "Cdagdn", b.s2, "Cdn", b.s1

H = MPO(ampo, sites)

By the way, my julia version is 1.6.2 and I am using a AMD CPU if that matters.

Probably i'm missing something, i'm grateful with any help ! Thanks !

commented by (14.1k points)
Thanks for the report, I'm seeing the same thing. It should be a very simple fix, I'll work on it as soon as I have some time.
commented by (190 points)
Thank you Matthew :)

1 Answer

+1 vote
answered by (14.1k points)

This should be fixed on the latest version (0.2.7).

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