LINEQN_solver

Default: LINEQN_solver = 'BCX2'

option	description
'BiCG'	BiCGstab, using matrix-times-vector emulation for the big system (i.e. do not construct the linear system explicitly, but provide a subroutine that computes the result of the matrix-vector-operation)
'BCG2'	BiCGstab(2), using matrix-times-vector-emulation
'BCX1'	BiCGstab, explicitly construct the matrix (takes more memory)
'BCX2'	BiCGstab(2), explicitly construct the matrix (faster, but takes more memory), default
'SAMG'	Algebraic Multigrid method from the SAMG-solver library, Fraunhofer SCAI
'BCGL'	BiCGstab(l), using matrix-times-vector emulation, experimental , see also BCGSL_ell

Expert option: auto-chooser 'AUTO:xxxx:yyyy:n:m' -> automatically choose the fastest option between 2 solvers xxxx and yyyy from the list After |n| time steps of one solver a full comparison is carried out. If n is positive, in addition the solver is immediately switched if the current option is slower than the last known timing of the other solver. Allow the failure of a solver for m time steps before re-testing The numbers n and m have to be 4-digit-characters, including sign . If the Output Level >=3, the user is informed about the timings as well as the decisions of the automatic solver control. More information: BiCGstab, BiCGstab(2) and BiCGstab(l), SAMG.