+1 vote
asked by (200 points)
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I'm trying to define my own SiteSet, basing on Hubbard (with two orbitals per site, and possibly an additional quantum number related to orbitals). The code compiles, but after running DMRG I get a segfault in first sweep. Depending on my initial state, I get it on different stages of first sweep. When running in debug mode, I get:

dmrg-g: /home/varelse/programs/itensor/itensor/itdata/qutil.h:190: void itensor::loopContractedBlocks(const BlockSparseA&, const IQIndexSet&, const BlockSparseB&, const IQIndexSet&, BlockSparseC&, const IQIndexSet&, Callable&) [with BlockSparseA = itensor::QDense; BlockSparseB = itensor::QDense; BlockSparseC = itensor::QDense; Callable = itensor::doTask(itensor::Contract&, const itensor::QDense&, const itensor::QDense&, itensor::ManageStore&) [with VA = double; VB = double]::<lambda(itensor::DataRange, const Labels&, itensor::DataRange, const Labels&, itensor::DataRange, const Labels&)>; itensor::IQIndexSet = itensor::IndexSetT]: Assertion `cblock' failed.

What could this error possibly mean?

(EDIT: I found the error - I defined my physical state IQIndex so that it had two subspaces of equal quantum numbers. )

1 Answer

0 votes
answered by (70.1k points)

Hi - glad to see you're trying some of the advanced features and that you found the error in your code. Let me know if you run into any other issues where I can help.


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