TeNPy Forum

I did not notice that in the more recent version (0.8.4), the simulation module exactly enables the resume from checkpoints. The logger system has also been updated and completely moved to the simulation module. Thanks for the author.

My question is related to "circumvent" time-wall of computer clusters. If principle, we can save data before the hitting the time-wall and start a new job to continue the calculation with the data. However, my experience is that for iDMRG, only saving the MPS (psi) is not efficient enough....

You just need to find that for ground state. For correlation length in iDMRG, you can find the theory for critical chains. https://link.aps.org/doi/10.1103/PhysRevLett.102.255701 For gaped chains, correlation length should simply converge when you increase bond dimension. Correlation length xi=v/gap...

Sorry for not understanding you question. "segment" is what you need.

To see if there is a neutral gap, there is an alternative way free of edge effect. You may run infinite DMRG with different bond dimensions and print mps.correlation_length () for different bond dimensions. Plotting correlation_length vs bond dimensions using log-log scale and a convergence tendency...

Perhaps you want to use mps.correlation_function(ops1, ops2, sites1=None, sites2=None, opstr=None, str_on_first=True, hermitian=False, autoJW=True) See https://tenpy.readthedocs.io/en/latest/reference/tenpy.networks.mps.MPS.html?highlight=correlation#tenpy.networks.mps.MPS.correlation_function For e...