Dear there, I have a quick question about if it possible to store MPS in the middle of 1 sweep, I mean before one sweep finishes. Becasue the cluster I’m using has 24-hour time limit, and the system I’m calculating is a bit complicated which requires roughly 30 hours for even 1 sweep… So just wonde…

Thanks for your reply!! I’ve read the suggestion there and want to double check my understanding. I saw by overloading the measure! function with an observer, I can print out psi, bond, energy etc during each sweep, then would the idea be: I print and save the wavefunction to h5 after each bond opti…

A few comments: A word of caution: you can decide how often you want to save the MPS, as depending on the size/speed of the writing the hdf5 file, lost calculations may be faster to redo than to save constantly. If the DMRG optimization hasn’t finished the 20th bond optimization then it won’t have…

Oh I see! So the intermediate psi is used as a better initial MPS for next DMRG calculation, the idea is not to continue the previous one from exactly where it was interrupted, is this right? And thanks for reminding me I can change the frequency of saving! I try to write a short function that save…

Looks good to me! And yes, trying to save whatever has been partially “swept” as a better start to your restart. And let me recommend the do open syntax since its safer: h5open("wavefunction.h5","w") do f write(f,"PGS",psi) end

Thank you for confirming and letting me know this safer way for saving!

I got one more problem…I tried the following(attached), basically what we’ve discussed, but I receive an error message saying: ERROR: LoadError: type NamedTuple has no field bond. Do you happen to know what does this mean? (I feel it means I don’t kwargs bond, but I don’t why…) The complete error me…

You explicitly listed bond as an argument to ITensors.measure! so it won’t show up in the remainder of the splatted kwargs.... In fact, you can see the if statement already uses it so you can just remove the line bond = kwargs[:bond] and things should work. I suspect if you had written it as ITensor…

Can MPS be stored to h5 in the midst of a sweep?

ITensor Julia Questions

ryanlevy July 31, 2023, 7:45am 2

See the discussion here for one possible solution

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Can MPS be stored to h5 in the midst of a sweep?

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