I’m using the AGP from ITensoragp, at the moment of using the linsolve function I get the following error: ERROR: MethodError: no method matching axpy!(::ComplexF64, ::MPS, ::MPS) . Previously I didn’t have this issue, so I’m not sure if there was an update or something that now doesn’t allow to use…

Hi yes, will try to be more clear: I’m essentially using this: As,ls_error = agp(HMPOsl[ii], ∂λH,As; error = false,tol=1e-6, maxiter=kwsweeps, krylovdim=kwmaxdim) where HMPOsl[iii] is an MPO Hamiltonian, also ∂λH is an MPO, and As is some initial ansatz obtained by nested commutator. By using what…

Again, please read: Please Read: Make It Easier to Help You , please format your code and share a single code block that we could copy and paste and run to reproduce the error you are getting, and share all of the versions you are using (the versions of the packages you are using and the Julia versio…

I’m not just trying to be nitpicky or difficult, following those instructions makes it a lot easier for one of us or other users of the forum to help you. Putting in a bit more work on your end when you construct your post lowers the barrier for us to help.

To be more specific, there are a lot of undefined variables in your code, like HMPOsl, ∂λH, etc. Just sharing the types of those objects is not enough, please share a code where you show all of the packages you have loaded, the construction of all of the objects you are using which are needed to run…

Hi, yes, I understand. The thing is I use a large number of libraries so it makes it a bit difficult to share all the necessary code. To make it simple, let’s say I literally want to run the example you have on ( ITensorAGP.jl/src/agp.jl at main · ITensor/ITensorAGP.jl · GitHub ) this: using ITensors…

Thanks for trying to include a minimal runnable example. This minimal example works for me and I don’t see the error you are reporting: using ITensorAGP: agp using ITensorMPS: MPO, OpSum, siteinds function main(; n, hz, nsweeps) s = siteinds("Qubit", n) os = OpSum() for j in 1:(n - 1) o…

Looking back at your error message, I believe the issue you are seeing may be caused by the fact that you are not loading ITensorAGP.jl or ITensorMPS.jl. We overload KrylovKit.linsolve for MPS/MPO objects in ITensorTDVP.jl, which is used by ITensorMPS.jl and in turn by ITensorAGP.jl. If you don’t l…

Instead of copying and pasting the agp function definition into your own project, you should instead install ITensorAGP.jl as instructed here: GitHub - ITensor/ITensorAGP.jl: Adiabatically evolve matrix product states (MPS) using matrix produect operator (MPO) representations of the adiabatic gauge …

Hi Matthew, thanks for all the help. The problem is that I had conflicting versions that involved PastaQ, ITensors, ITensorAGP, and didn’t allow me to install ITensorsMPS. I manage to solve this and now everything works alright. Will try to be more concrete about my question and examples next time. …

Problem using linsolve

ITensor Julia Questions

mtfishman May 31, 2024, 3:47pm 2

Please read: Please Read: Make It Easier to Help You for a guide on asking questions on this forum. Can you share a minimal self-contained code that reproduces the error that you are seeing as well as the versions of all of the packages and Julia version you are using?

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Problem using linsolve

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