Enum Error 

pub enum Error {
    Input(String),
    Drift {
        eps: f64,
    },
    NoAbsorber {
        eps: f64,
    },
    LostProbability {
        units: usize,
    },
    Internal(String),
}

Why a procedure refused to run, or could not finish.

Refusals are loud on purpose: a sampling procedure that silently mends its input produces a sample whose inclusion probabilities nobody knows, and the weights built from them estimate nothing.

Variants

Input(String)

The input cannot define a valid selection — a negative size, a uniform outside [0, 1), mismatched lengths. The message says which.

Drift

The expected hits summed too far from an integer to be a sample size: the drift exceeds the procedure’s tolerance of 1e-8, so the caller’s expected hits do not add to a whole number of selections.

Fields

eps: f64

NoAbsorber

The floating-point drift could not be absorbed: no unit has a fractional expected hit large enough to take the correction.

Fields

eps: f64

LostProbability

After the corrections, units with positive expected hits were left with no probability of selection at all. Their weights would be infinite; the selection is refused instead.

Fields

units: usize

Internal(String)

The procedure’s own accounting failed — realised hits that do not add to the sample size. This is a bug in the crate, not in the input; please report it.

Trait Implementations

impl Clone for Error

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Error

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

Formats the value using the given formatter.

impl Display for Error

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

Formats the value using the given formatter.

impl Error for Error

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl PartialEq for Error

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Error