Search found 436 matches
- 31 Aug 2018, 09:50
- Forum: Implementations
- Topic: Parallel iDMRG with mpi4py
- Replies: 6
- Views: 23101
Re: Parallel iDMRG with mpi4py
Am I right that one has to reload preloaded modules like numpy/scipy after setting the number of threads or is there any other way to do that? I don't think you need to reload scipy or numpy. It's still the same library, using the same underlying MKL, it's just a sinlge parameter, which can be chan...
- 30 Aug 2018, 12:43
- Forum: Implementations
- Topic: Parallel iDMRG with mpi4py
- Replies: 6
- Views: 23101
Re: Parallel iDMRG with mpi4py
Hi Mirco, I see, so they are basically the same in the limit of half as many nodes as sites. I wonder whether the full parallelization of Ueda's approach requires more or less iterations/sweeps to reach convergence. As far as I see, compared to the sweeping it needs more (two-site) updates to carry ...
- 29 Aug 2018, 10:09
- Forum: Implementations
- Topic: Parallel iDMRG with mpi4py
- Replies: 6
- Views: 23101
Re: Parallel iDMRG with mpi4py
Hey Mirco, parallelization of DMRG is a great idea which will probably benefit many people! Using mpi4py seems a good idea to me. As you said, it's included in the intel python distribution, and also in the anaconda distribution - these two are the recommended ones in the installation instructions, ...
- 29 Aug 2018, 09:15
- Forum: HowTos and FAQ for TeNPy
- Topic: Different coupling terms on different sites
- Replies: 5
- Views: 11005
Re: Different coupling terms on different sites
As we are contracting the entire MPS to calculate for energy, is my understanding correct in saying that it does not matter which site we choose in this case? Yes, that's correct! Based on what I understand, iDMRG can still be calculated for such a system but the only way to obtain the energy is di...
- 28 Aug 2018, 15:50
- Forum: HowTos and FAQ for TeNPy
- Topic: Different coupling terms on different sites
- Replies: 5
- Views: 11005
Re: Different coupling terms on different sites
Taking the energy as returned by the DMRG code is a perfectly reasonable thing ;-) And it's what I would recommend you for now. In general, you could still try to get the energy from local expectation values and/or correlation functions, but you would need to carefully figure all the terms out and s...
- 27 Aug 2018, 15:04
- Forum: Implementations
- Topic: Lattice design issue
- Replies: 4
- Views: 19604
Re: Lattice design issue
On one hand I agree that this would be very cool to have an single "TFIModel" with some specified nearest neighbor couplings. On the other hand, I see some problems with that: When you only want to derive the Model from the MPOModel, this approach is fine, but what if you want to derive fr...
- 27 Aug 2018, 13:11
- Forum: Implementations
- Topic: MultiCouplingModel and Toric Code as example
- Replies: 7
- Views: 26879
Re: MultiCouplingModel and Toric Code as example
ok, which initial state and parameters are you using? Mixer enabled? I checked with the following code import numpy as np from tenpy.models.toric_code import ToricCode from tenpy.networks.mps import MPS from tenpy.algorithms import dmrg for Lx in [1, 2, 3, 4]: print("="*80) print("Lx ...
- 27 Aug 2018, 11:22
- Forum: Implementations
- Topic: MultiCouplingModel and Toric Code as example
- Replies: 7
- Views: 26879
Re: MultiCouplingModel and Toric Code as example
You're right, L_x is just the number of "rings" of the cylinder included into the MPS unit cell. I agree that the energy per site shouldn't depend on L_x, so it's a bad sign if it does, there's probably something wrong then
- 27 Aug 2018, 11:18
- Forum: HowTos and FAQ for TeNPy
- Topic: Different coupling terms on different sites
- Replies: 5
- Views: 11005
Re: Different coupling terms on different sites
To answer first in general (That's the perfect place to ask this ;-)): If you give the strength parameter to add_coupling , it is tiled to the "correct" size of the couplings. You are right, for onsite terms in add_onsite , this is simply the Ls of the lattice. Now what is the "correc...
- 23 Aug 2018, 15:56
- Forum: Implementations
- Topic: MultiCouplingModel and Toric Code as example
- Replies: 7
- Views: 26879
MultiCouplingModel and Toric Code as example
Since I've recently added the MultiCouplingModel , it's time to add a simple model actually using it. I think the exactly solvable toric code is a good example, so here is my implementation: """Kitaev's exactly solvable toric code model. As we put the model on a cylinder, the name &qu...
- 22 Jul 2018, 23:16
- Forum: Other News
- Topic: We got a forum!
- Replies: 0
- Views: 20277
We got a forum!
It's a bit wired to make the announcement that I've set up this forum in this forum, but I guess that's the first thing to announce to the world once this forum is set up
Anyways, I'm awaiting your questions, suggestions and contributions. Happy posting!
Anyways, I'm awaiting your questions, suggestions and contributions. Happy posting!