Struct StreamingStatistics 

pub struct StreamingStatistics {
    pub count: usize,
    pub null_count: usize,
    pub min: f64,
    pub max: f64,
    /* private fields */
}

Fields

count: usize

null_count: usize

min: f64

max: f64

Implementations

impl StreamingStatistics

pub fn new() -> Self

pub fn with_sample_capacity(max_sample: usize) -> Self

pub fn update(&mut self, value: &str)

pub fn merge(&mut self, other: &StreamingStatistics)

pub fn mean(&self) -> f64

pub fn variance(&self) -> f64

pub fn std_dev(&self) -> f64

pub fn unique_count(&self) -> usize

Distinct non-null values, exact until the estimator spills.

This used to count the reservoir when it held every value and fall back to a sketch otherwise, so any column longer than the reservoir, even one with a single value, reported an approximate count, and a different one from the engines that use the shared estimator.

pub fn unique_count_is_approximate(&self) -> bool

pub fn unique_count_lower_bound(&self) -> usize

See CardinalityEstimator::distinct_lower_bound.

pub fn spill_distinct(&mut self)

Answer distinct counts from the sketch from here on, freeing the exact set. For memory pressure; the count is then reported approximate.

pub fn exact_distinct_bytes(&self) -> usize

Heap held by the exact distinct set: zero once it has spilled, and zero for a column that has seen no value, so spilling it would free nothing.

pub fn sample_values(&self) -> &[String]

pub fn date_match_count(&self) -> usize

Values over the full stream accepted by the temporal calculator.

pub fn exact_numeric_aggregates(&self) -> Option<ExactNumericAggregates>

Exact aggregates over every numeric value this column has streamed, or None when no value parsed as a finite number.

These come from the O(1)-memory min/max fields and the Welford accumulator, so they cover the full stream even when the reservoir sample no longer does.

pub fn text_length_stats(&self) -> TextLengthStats

pub fn reduce_sample_capacity(&mut self)

pub fn memory_usage_bytes(&self) -> usize

Trait Implementations

impl Clone for StreamingStatistics

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 StreamingStatistics

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

Formats the value using the given formatter.

impl Default for StreamingStatistics

fn default() -> Self

Returns the “default value” for a type.