Enum InitError 

pub enum InitError {
    NoSamples,
    InvalidInterval {
        interval: Seconds,
    },
    InvalidStep {
        dt: Seconds,
    },
    NotFinite,
    InvalidVariance,
}

Why initialization could not run at all.

Distinct from Coarse: these are inputs the filter can make nothing of, not starts of lower quality. Every one of them is the caller handing over something broken, which is why they are checked rather than trusted — a seed in particular crosses a boundary the filter does not control, arriving from another estimator or from storage that may be stale or corrupt.

Variants

NoSamples

The window held no samples, so there is nothing to align from.

InvalidInterval

A sample’s integration interval was under a microsecond, so it covers no span of time to measure the window over or divide its increments by. One that is not a number is NotFinite.

Fields

interval: Seconds

The interval offered.

InvalidStep

A sample was timed no later than the one before it, so the window’s timestamps say nothing about when it ended, which is where the filter’s clock starts. As Propagation::InvalidStep for a step.

Fields

dt: Seconds

The time from the previous sample to this one.

NotFinite

A measurement, state, or covariance carried a value that is not finite.

InvalidVariance

A seed covariance had a variance on its diagonal that no prior has: below the floor of equation (42′), which includes zero and negative.

Zero is the one that arrives in practice, from a warm start deserialized out of storage that never populated the diagonal. It reads as a tight prior and is not one: it claims perfect knowledge, so the gain K = P Hᵀ S⁻¹ of equation (25) is zero for that quantity and no measurement ever corrects it, while Validity compares the zero variance against Config::accuracy and reports the quantity good from the first read. A negative variance claims better than perfect.

The bar is the floor rather than zero because zero is only the tidiest member of that class: the same accident with an exponent left in it arrives at 1e-30 and is indistinguishable in f32 — the gain is still zero and the quantity still reads good from the first epoch. A seed is the one path that writes a covariance in whole, so it is refused here where a reset_*_to writing one block is floored instead. See Fusion::InvalidNoise for the bar every fuse_* puts on R, which is still strict positivity.

Symmetry is imposed by (42) rather than checked, and positive-definiteness is not checked: that is a factorization on the caller’s data, not a guard.

Trait Implementations

impl Clone for InitError

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 InitError

impl Debug for InitError

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

Formats the value using the given formatter.

impl Display for InitError

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

Formats the value using the given formatter.

impl Error for InitError

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 Format for InitError

where Seconds: Format,

Available on crate feature defmt only.

fn format(&self, f: Formatter<'_>)

Writes the defmt representation of self to fmt.

impl From<SampleRefusal> for InitError

fn from(refusal: SampleRefusal) -> Self

Converts to this type from the input type.

impl PartialEq for InitError

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for InitError