follow bug28, 1. the bug with slover_parity is cleared, the matvec_eo (or matvec_oe) is equal to -kappa*D_eo (or D_oe), so the right matvec_parity is little different to 1-166 (PhD thesis of Jiang Xiangyu); 2. referring to PyQCU/examples/init/log-v20260222.txt, the multi-threaded version of parity solver (pyqcu::testing::solver::parity) pass. :)