Struct GmresOptions 

pub struct GmresOptions {
    pub rtol: f64,
    pub atol: f64,
    pub restart: usize,
    pub max_iterations: usize,
}

Accuracy and memory budget of restarted GMRES.

The solve converges when the true residual norm is at most max(atol, rtol * |b|). The defaults are rtol = 1e-10, atol = 0, restart = 30 and max_iterations = 300; the Python constants iterative.DEFAULT_RTOL, DEFAULT_ATOL, DEFAULT_RESTART and DEFAULT_MAX_ITERATIONS repeat them.

Fields

rtol: f64

Relative residual tolerance with respect to the right-hand side norm.

atol: f64

Absolute residual tolerance, for right-hand sides near zero.

restart: usize

Maximum number of Krylov vectors retained before a restart.

max_iterations: usize

Maximum total operator applications in the Arnoldi iterations.

Implementations

impl GmresOptions

pub(crate) fn for_derivative(self) -> Self

Derivative right-hand sides have arbitrary scale, so an absolute tolerance would incorrectly erase small tangents or cotangents. Keep the relative tolerance, or use the default when the primal requested absolute-only convergence; the restart and iteration budgets stay unchanged.

pub(crate) fn validate(self) -> Result<()>

Reject non-finite or negative tolerances, two zero tolerances, and a zero restart length or iteration limit.

Trait Implementations

impl Clone for GmresOptions

fn clone(&self) -> GmresOptions

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for GmresOptions

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for GmresOptions

fn default() -> Self

Returns the “default value” for a type.

impl Copy for GmresOptions