Struct MinProblem 

pub struct MinProblem {
    pub lo: f64,
    pub hi: f64,
}

One bracketed 1-D extremum problem: an interval believed to contain a single interior extremum of the objective.

Fields and valid ranges

• lo, hi — the bracket. Both must be finite, or the lane reports MinStatus::InvalidBracket. They may be given in either order; the kernel normalises, exactly as crate::math::parallel::RootProblem does. A degenerate bracket (lo == hi) converges immediately at that point with zero iterations, which is truthful: a zero-width bracket has already met any non-negative tolerance.

The precondition golden section cannot check

The objective must be unimodal on [lo, hi] — one interior extremum, no second basin. This is a precondition on the caller, not something the kernel verifies; see the module-level warning. Note that a monotone objective on the bracket is a benign special case: the contraction walks to the appropriate endpoint and converges there, which is the intended behaviour when the real extremum lies just outside. It is the multimodal case that is dangerous, because the answer looks exactly like a correct one.

There is no guess field, unlike crate::math::parallel::RootProblem. Golden section is driven entirely by the bracket and has nowhere to put a starting iterate; a method that could use one (Brent’s parabolic interpolation) is deliberately not implemented here — again, see the module docs.

Units

Dimensionless f64 in whatever units the caller’s abscissa carries — pascals for a choke-pressure search, dimensionless for a blend factor. See the module-level “Units” section.

Example

use outram_foam_basic_lib::math::minimise::MinProblem;

let p = MinProblem::new(0.0, 1.0);
assert_eq!(p.width(), 1.0);

// Either order is accepted; the width is still positive.
let q = MinProblem::new(1.0, 0.0);
assert_eq!(q.width(), 1.0);

Fields

lo: f64

One end of the bracket. Finite; need not be less than hi.

hi: f64

The other end of the bracket. Finite; need not be greater than lo.

Implementations

impl MinProblem

pub fn new(lo: f64, hi: f64) -> Self

A problem bracketed on [lo, hi].

Arguments

• lo, hi — the bracket ends, finite, in either order.

pub fn width(&self) -> f64

The bracket width |hi - lo|, in the abscissa’s units.

NaN if either end is NaN; infinite if either end is infinite. Both of those cases are rejected as MinStatus::InvalidBracket by the kernel.

Trait Implementations

impl Clone for MinProblem

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for MinProblem

impl Debug for MinProblem

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

Formats the value using the given formatter.

impl PartialEq for MinProblem

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for MinProblem