Reading MPS from mps.h5 that contains complex numbers

Question

Hi Miles,

I used

f = h5open("mps.h5","r")
psi = read(f,"mps",MPS)

to read the ground state MPS from the file mps.h5. However, I got the error:
"ERROR: LoadError: HDF5 group or file does not contain BlockSparse{Complex{Float64}} data"

Is this because the file contains complex numbers? I tried with real MPS and it worked out fine. If this is the case, then is there a way around this?

Thanks a lot for your time,
-Mason

Comments

Hi Mason, what version of ITensor are you using? I ask because I only finished implementing this feature very recently, though there may be some cases still missing.

Also, how did you create the file MPs.h5? Did the tensors used to create it contain complex numbers?

Thank you, Miles

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The version I'm using is v0.1.41. To create the mps.h5 file, I used
f = h5open("mps.h5","w")
write(f,"mps",psi)
close(f)
Thank you

---

Hi Mason,

You should upgrade to the latest version of ITensors.jl (v0.2.6), since new HDF5 reading and writing features were added in recent releases. You can see a succinct list of recent changes in the NEWS.md file here: https://github.com/ITensor/ITensors.jl/blob/main/NEWS.md#itensor-v026-release-notes which is helpful for seeing if there were any changes to features you are interested in.

If you upgrading your code causes any errors, please try to follow the upgrade guide (https://itensor.github.io/ITensors.jl/stable/UpgradeGuide_0.1_to_0.2.html).

-Matt

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Hi Matt, thanks a lot, this is really helpful. Everything worked out fine after the update and some minor changes in the code.

Answer 1

Answer is in the comment above.