Struct IsmvParams 

pub struct IsmvParams {
    pub variant: IsmvVariant,
    pub tol: f64,
    pub max_iter: Option<usize>,
    pub radius: Option<f64>,
}

iSMV parameters. The defaults are Wen et al. 2014’s with the lab’s iSMV.m (see the module docs); IsmvParams::qsmjl gives QSM.jl’s.

Fields

variant: IsmvVariant

The implementation to reproduce (default IsmvVariant::Wen2014).

tol: f64

Stopping tolerance; finite and > 0. IsmvVariant::Wen2014: stop when the relative change between successive iterates, ‖F₁ − F₂‖/‖F₁‖, falls below it (default 5e-5, Wen et al. 2014; iSMV.m hard-codes 0.001). IsmvVariant::QsmJl: stop when the residual falls to this fraction of the first one (QSM.jl’s tol, 1e-3).

max_iter: Option<usize>

Iteration cap; None (the default) is none, as in iSMV.m. QSM.jl’s maxit is 500.

radius: Option<f64>

Sphere radius in mm, finite and > 0; None (the default) is the variant’s default: 6 voxels for IsmvVariant::Wen2014 (Wen et al. 2014), 2 · max(voxel size) for IsmvVariant::QsmJl. See IsmvParams::radius_mm. Before 2026-10-29 the default was QSM.jl’s, and before 2026-10-28 5 mm with tol 1e-6 and 50 iterations, which had no reference.

Implementations

impl IsmvParams

pub const WEN2014_TOL: f64 = 5e-5

Wen et al. 2014’s stopping tolerance on the relative change between iterates.

pub const WEN2014_RADIUS_VOXELS: f64 = 6.0

Wen et al. 2014’s radius in voxels (of the smallest voxel dimension).

pub const QSMJL_RADIUS_VOXELS: f64 = 2.0

QSM.jl ismv’s default kernel radius as a multiple of the largest voxel dimension.

pub fn qsmjl() -> Self

QSM.jl ismv at its own defaults: IsmvVariant::QsmJl, tol 1e-3, maxit 500, r = 2 · max(voxel size).

pub fn radius_mm(&self, grid: &Grid) -> f64

The sphere radius in mm on grid: radius, or the variant’s default (6 · min(voxel size) for IsmvVariant::Wen2014, 2 · max(voxel size) for IsmvVariant::QsmJl).

pub fn validate(&self) -> Result<(), InputError>

Checks what iSMV cannot run with: tol and the radius must be finite and > 0 (at tol 0 and no cap the iteration would not end).

Trait Implementations

impl Clone for IsmvParams

fn clone(&self) -> IsmvParams

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for IsmvParams

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

Formats the value using the given formatter.

impl Default for IsmvParams

fn default() -> Self

Returns the “default value” for a type.

impl Serialize for IsmvParams

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.