Struct MedianGroupsAccumulator 

struct MedianGroupsAccumulator<T: ArrowNumericType + Send> {
    data_type: DataType,
    group_values: Vec<Vec<T::Native>>,
}

The median groups accumulator accumulates the raw input values

For calculating the accurate medians of groups, we need to store all values of groups before final evaluation. So values in each group will be stored in a Vec<T>, and the total group values will be actually organized as a Vec<Vec<T>>.

Fields

data_type: DataType

group_values: Vec<Vec<T::Native>>

Implementations

impl<T: ArrowNumericType + Send> MedianGroupsAccumulator<T>

pub fn new(data_type: DataType) -> Self

Trait Implementations

impl<T: Debug + ArrowNumericType + Send> Debug for MedianGroupsAccumulator<T>

where T::Native: Debug,

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

Formats the value using the given formatter.

impl<T: ArrowNumericType + Send> GroupsAccumulator for MedianGroupsAccumulator<T>

fn update_batch( &mut self, values: &[ArrayRef], group_indices: &[usize], opt_filter: Option<&BooleanArray>, total_num_groups: usize, ) -> Result<()>

Updates the accumulator’s state from its arguments, encoded as a vector of [ArrayRef]s.

fn merge_batch( &mut self, values: &[ArrayRef], group_indices: &[usize], _opt_filter: Option<&BooleanArray>, total_num_groups: usize, ) -> Result<()>

Merges intermediate state (the output from [Self::state]) into this accumulator’s current state.

fn state(&mut self, emit_to: EmitTo) -> Result<Vec<ArrayRef>>

Returns the intermediate aggregate state for this accumulator, used for multi-phase grouping, resetting its internal state.

fn evaluate(&mut self, emit_to: EmitTo) -> Result<ArrayRef>

Returns the final aggregate value for each group as a single RecordBatch, resetting the internal state.

fn convert_to_state( &self, values: &[ArrayRef], opt_filter: Option<&BooleanArray>, ) -> Result<Vec<ArrayRef>>

Converts an input batch directly to the intermediate aggregate state.

fn supports_convert_to_state(&self) -> bool

Returns true if [Self::convert_to_state] is implemented to support intermediate aggregate state conversion.

fn size(&self) -> usize

Amount of memory used to store the state of this accumulator, in bytes.