Struct Filter 

pub struct Filter<F>
where
    F: Fn(&RecordBatch) -> Result<BooleanArray> + Send + Sync,
{ /* private fields */ }

A transform that filters rows based on a predicate.

The predicate function receives a RecordBatch and must return a BooleanArray with the same number of rows, where true indicates the row should be kept.

Example

use alimentar::Filter;
use arrow::array::{Int32Array, BooleanArray};

let filter = Filter::new(|batch| {
    let col = batch.column(0).as_any().downcast_ref::<Int32Array>().unwrap();
    let mask: Vec<bool> = (0..col.len()).map(|i| col.value(i) > 5).collect();
    Ok(BooleanArray::from(mask))
});

Implementations

impl<F> Filter<F>

where F: Fn(&RecordBatch) -> Result<BooleanArray> + Send + Sync,

pub fn new(predicate: F) -> Self

Creates a new Filter transform with the given predicate.

Trait Implementations

impl<F> Transform for Filter<F>

where F: Fn(&RecordBatch) -> Result<BooleanArray> + Send + Sync,

fn apply(&self, batch: RecordBatch) -> Result<RecordBatch>

Applies the transform to a RecordBatch.