-qps_mpgp_alpha_direct | - true sets expansion step length value directly, false (default) multiplier (typical between (0,2]) for step length equal to reciprocal of maximal eigenvalue | |
-qps_mpgp_alpha | - fixed step length value for expansion, default: 2.0 | |
-qps_mpgp_gamma | - proportionality constant | |
-qps_mpgp_maxeig | - approximate maximum eigenvalue of the Hessian (automatically computed by default) | |
-qps_mpgp_maxeig_tol | - relative tolerance for power method to find approximate maximum eigenvalue of the Hessian | |
-qps_mpgp_maxeig_iter | - number of iterations of power method to find an approximate maximum eigenvalue of the Hessian | |
-qps_mpgp_btol | - boundary overshoot tolerance, default: 10*PETSC_MACHINE_EPSILON" | |
-qps_mpgp_bound_chop_tol | - sets boundary to 0 for |boundary|<tol, default: 0 | |
-qps_mpgp_expansion_type | - set expansion step type, default: "std" | |
-qps_mpgp_expansion_length_type | - set expansion step length type, default: "fixed" | |
-qps_mpgp_alpha_reset | - if alpha=Nan reset to initial value, otherwise keep last alpaha, default: true | |
-qps_mpgp_fallback | - throw away expansion step if cost function increased and do a std expansion step, default false | |
-qps_mpgp_fallback2 | - same as fallback which is done only if the next step is proportioning |
"std" | - standard expansion | |
"projcg" | - unconstrained CG step projected back to feasible set | |
"gf" | - free gradient for both step length computation and expansion direction | |
"g" | - normal gradient for both step length computation and expansion direction | |
"gfgr" | - expansion in free gradient direction, steplength using reduced gradient | |
"ggr" | - expansion in normal gradient direction, steplength using reduced gradient |
"fixed" | - standard fixed step length | |
"opt" | - optimal step length |
"optapprox" | - (usually poor) approximation of optimal step length |
"bb" | - Barzilai-Borwein step length |