mps_optim writes states as a series of mpsXX.h5 files in s *chkp subdirectory. While this is convenient, I have encountered many situations when I wanted to do lots of computations, but the quantity number_of_vectors*chain_length was large to the point of crashing the filesystem or exceeding file number quotas.

While in all cases the problem is actually with the system (hard to persuade administrator, old file system), still my experience tells that the "de facto” usability could be icreased by limiting the number of files written per run (currently it is O(L), while O(1) would be more convenient).

On 24 Aug 2015, at 09:28, Michele Dolfi <dolfim@phys.ethz.ch> wrote:

Dear Mateusz,

Thanks for reporting that. I increased the checks, now the error message should be more consistent.

Best regards,
Michele

--
ETH Zurich
Michele Dolfi
Institute for Theoretical Physics
HIT G 32.4
Wolfgang-Pauli-Str. 27
8093 Zurich
Switzerland

dolfim@phys.ethz.ch
www.itp.phys.ethz.ch

+41 44 633 78 56 phone
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On Aug 22, 2015, at 6:07 PM, Mateusz Łącki <mateusz.lacki@gmail.com> wrote:

Dear All,
I wish to report a suboptimal behaviour in the mps_optim:

setting the initial state with wrong L (L=10 and there are 12 spins defined)

L=10;

init_state="local_quantumnumbers"
initial_local_S="0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5,0.5"
initial_local_Sz="0.5,-0.5,0.5,0.5,-0.5,0.5,-0.5,-0.5,0.5,-0.5,0.5,0.5”

produces a nasty segfault with no warning (in almost all other cases of setting something wrong a message explaining a nature of the problem is printed).
This is not a bug, but a nuissance.

Best,
Mateusz Łącki