0 votes
asked by (260 points)


I am facing a Segmentation fault error with the function expH (my goal is to simulate the dynamics of a spin boson hamiltonian with long-range interactions)

Please find below a minimal example which causes the crash:

It seems to be due to the interplay between the Complex argument Cplxi + the flip-flip terms Sm S_m..

Thanks for your help


int main(int argc, char* argv[])
auto sites = SpinHalf(3);
auto ampo = AutoMPO(sites);
ampo += "Sm",1,"Sm",2;
ampo += "Sp",1,"Sp",2;
ampo += "Sp",2,"Sp",3;
ampo += "Sm",2,"Sm",3;
auto H = MPO(ampo);
auto tau = 0.1;
auto expH = toExpH(ampo,tau*Cplx_i);
return 0;

commented by (680 points)
edited by
Hi Benoit,

Which version of ITensor are you using? Using version 2.0.11 retrieved on May 20, I can get the code running, provided that I change the toExpH line to

auto expH = toExpH<ITensor>(ampo,tau*Cplx_i);

Hope that helps!

commented by (260 points)
Hi Chengshu,

I had itensor 2.0.11 but I just installed the new version 2.1.0 and now it works.
Thanks a lot!


1 Answer

0 votes
answered by (70.1k points)

Marking this as answered because of the discussion above. Thanks Chengshu!

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