Trait CardinalitySketch 

pub trait CardinalitySketch: Sketch {
    // Required methods
    fn estimate(&self) -> f64;
    fn error_bounds(&self, confidence: f64) -> ErrorBounds;
    fn relative_error(&self) -> f64;

    // Provided method
    fn estimate_with_bounds(&self) -> ErrorBounds { ... }
}

Cardinality (distinct count) estimation sketches

Required Methods

fn estimate(&self) -> f64

Estimate number of distinct items seen

fn error_bounds(&self, confidence: f64) -> ErrorBounds

Get error bounds at given confidence level (0.0 to 1.0)

fn relative_error(&self) -> f64

Relative standard error (RSE) of the estimate

RSE = standard_error / true_value ≈ 1.04 / sqrt(m) for HLL

Provided Methods

fn estimate_with_bounds(&self) -> ErrorBounds

Estimate with default 95% confidence bounds

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl CardinalitySketch for HyperLogLog

Available on crate feature cardinality only.