vortex-btrblocks 0.74.0

BtrBlocks style compressor
Documentation 
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// SPDX-License-Identifier: Apache-2.0
// SPDX-FileCopyrightText: Copyright the Vortex contributors

//! Pco (pcodec) float compression.

use vortex_array::ArrayRef;
use vortex_array::Canonical;
use vortex_array::ExecutionCtx;
use vortex_array::IntoArray;
use vortex_compressor::estimate::CompressionEstimate;
use vortex_compressor::estimate::DeferredEstimate;
use vortex_error::VortexResult;

use crate::ArrayAndStats;
use crate::CascadingCompressor;
use crate::CompressorContext;
use crate::Scheme;

/// Pco (pcodec) compression for floats.
#[derive(Debug, Copy, Clone, PartialEq, Eq)]
pub struct PcoScheme;

impl Scheme for PcoScheme {
    fn scheme_name(&self) -> &'static str {
        "vortex.float.pco"
    }

    fn matches(&self, canonical: &Canonical) -> bool {
        canonical.dtype().is_float()
    }

    fn expected_compression_ratio(
        &self,
        _data: &ArrayAndStats,
        _compress_ctx: CompressorContext,
        _exec_ctx: &mut ExecutionCtx,
    ) -> CompressionEstimate {
        CompressionEstimate::Deferred(DeferredEstimate::Sample)
    }

    fn compress(
        &self,
        _compressor: &CascadingCompressor,
        data: &ArrayAndStats,
        _compress_ctx: CompressorContext,
        exec_ctx: &mut ExecutionCtx,
    ) -> VortexResult<ArrayRef> {
        Ok(vortex_pco::Pco::from_primitive(
            data.array_as_primitive(),
            pco::DEFAULT_COMPRESSION_LEVEL,
            8192,
            exec_ctx,
        )?
        .into_array())
    }
}