common_solver_opts.md

Common Solver Options (Keyword Arguments for Solve)

While many algorithms have specific arguments within their constructor, the keyword arguments for solve are common across all the algorithms in order to give composability. These are also the options taken at init time. The following are the options these algorithms take, along with their defaults.

General Controls

• alias::LinearAliasSpecifier: Holds the fields alias_A and alias_b which specify whether to alias the matrices A and b respectively. When these fields are true, A and b can be written to and changed by the solver algorithm. When fields are nothing the default behavior is used, which is to default to true when the algorithm is known not to modify the matrices, and false otherwise.
• verbose: Whether to print extra information. Defaults to false.
• assumptions: Sets the assumptions of the operator in order to effect the default choice algorithm. See the [Operator Assumptions page for more details](@ref assumptions).

Iterative Solver Controls

Error controls are not used by all algorithms. Specifically, direct solves always solve completely. Error controls only apply to iterative solvers.

• abstol: The absolute tolerance. Defaults to √(eps(eltype(A)))
• reltol: The relative tolerance. Defaults to √(eps(eltype(A)))
• maxiters: The number of iterations allowed. Defaults to length(prob.b)
• Pl,Pr: The left and right preconditioners, respectively. For more information, see [the Preconditioners page](@ref prec).