Enum ClassReason 

pub enum ClassReason {
    NoNonlinearParts,
    NonlinearPartsCancelled,
    ObjectiveNotQuadratic,
    ConstraintNotQuadratic {
        row: usize,
    },
    ObjectiveTermsDropped,
    ConstraintTermsDropped {
        row: usize,
    },
    ObjectiveHessianIndefinite,
    NonconvexQcqp {
        row: usize,
    },
    ConstraintSenseNonconvex {
        row: usize,
    },
    ConstraintHessianIndefinite {
        row: usize,
    },
    QcqpReformTooCostly {
        flops: u128,
    },
    QcqpTooLargeToSolve {
        size: u64,
    },
    ConvexQuadraticObjective,
    ConvexQcqpWithinBudgets {
        flops: u128,
        size: u64,
    },
}

Why classify_problem reached the class it did.

Every arm is a place the classifier stops — either because it proved a class or because it could not, and fell back to the more general one. The distinction matters most for a convex QCQP: four different findings (a nonconvex row, a nonconvex sense, an unaffordable reformulation, an oversized conic solve) all route to Nlp, and a user staring at Problem class: NLP on a model they know is a QCQP has so far had no way to tell which. POUNCE_DBG_CLASSIFY=1 prints it.

Variants

NoNonlinearParts

Neither the objective nor any row carries a nonlinear part.

NonlinearPartsCancelled

Nonlinear parts exist but all of them expanded to nothing of degree 2 or higher — the model is linear after expansion.

ObjectiveNotQuadratic

The objective’s nonlinear part is not a degree-2 polynomial.

ConstraintNotQuadratic

Row row’s nonlinear part is not a degree-2 polynomial.

Fields

row: usize

ObjectiveTermsDropped

The objective is degree ≤ 2, but the recognizer lost a term reaching its coefficients, so they are not the whole objective.

ConstraintTermsDropped

Row row is degree ≤ 2, but the recognizer lost a term reaching its coefficients, so they are not the whole row (gh #685).

“Lost”, not merely “dropped”: a term that cancels exactly is not missing from the form, so those rows keep the fast path (gh #687).

Fields

row: usize

ObjectiveHessianIndefinite

The sense-adjusted objective Hessian has a negative eigenvalue, and every constraint row is linear — a nonconvex QP.

NonconvexQcqp

The sense-adjusted objective Hessian has a negative eigenvalue and some row carries curvature — a nonconvex QCQP, which is not a QP and must not be classified as one (see ProblemClass::NonconvexQp).

Fields

row: usize

ConstraintSenseNonconvex

Row row is quadratic with a PSD Hessian, but its bound sense (>=, =, or two-sided) carves a nonconvex feasible set.

Fields

row: usize

ConstraintHessianIndefinite

Row row’s quadratic Hessian is not PSD.

Fields

row: usize

QcqpReformTooCostly

Convex QCQP, but the cone reformulation exceeds [SOCP_REFORM_FLOP_BUDGET].

Fields

flops: u128

QcqpTooLargeToSolve

Convex QCQP whose reformulation is affordable, but whose conic solve exceeds [SOCP_SOLVE_SIZE_CAP].

Fields

size: u64

ConvexQuadraticObjective

Convex quadratic objective, linear constraints.

ConvexQcqpWithinBudgets

Convex QCQP inside both guards — the conic path is taken.

Fields

flops: u128

size: u64

Implementations

impl ClassReason

pub fn explain(self) -> String

One-line explanation, for the POUNCE_DBG_CLASSIFY log.

Trait Implementations

impl Clone for ClassReason

fn clone(&self) -> ClassReason

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ClassReason

impl Debug for ClassReason

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

Formats the value using the given formatter.

impl Eq for ClassReason

impl PartialEq for ClassReason

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ClassReason