Struct MaxAccumulator

pub struct MaxAccumulator { /* private fields */ }

An accumulator to compute the maximum value

Implementations

impl MaxAccumulator

pub fn try_new(datatype: &DataType) -> Result<Self>

new max accumulator

Trait Implementations

impl Accumulator for MaxAccumulator

fn update_batch(&mut self, values: &[ArrayRef]) -> Result<()>

Updates the accumulator’s state from its input.

fn merge_batch(&mut self, states: &[ArrayRef]) -> Result<()>

Updates the accumulator’s state from an Array containing one or more intermediate values.

fn state(&mut self) -> Result<Vec<ScalarValue>>

Returns the intermediate state of the accumulator, consuming the intermediate state.

fn evaluate(&mut self) -> Result<ScalarValue>

Returns the final aggregate value, consuming the internal state.

fn size(&self) -> usize

Returns the allocated size required for this accumulator, in bytes, including Self.

fn retract_batch( &mut self, _values: &[Arc<dyn Array>], ) -> Result<(), DataFusionError>

Retracts (removed) an update (caused by the given inputs) to accumulator’s state.

fn supports_retract_batch(&self) -> bool

Does the accumulator support incrementally updating its value by removing values.

impl Debug for MaxAccumulator

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

Formats the value using the given formatter.