Struct VarVecBuilder 

pub struct VarVecBuilder<T: Storable, E: Endianness> { /* private fields */ }

A builder for creating an VarVec from a slice of integers.

This builder is the primary entry point for constructing a compressed vector when the data is already available in memory. It allows for detailed configuration of the sampling rate (k) and the compression codec.

This builder always produces an owned VarVec. It is obtained by calling VarVec::builder.

Implementations

impl<T: Storable, E: Endianness> VarVecBuilder<T, E>

pub fn k(self, k: usize) -> Self

Sets the sampling rate k for random access.

The sampling rate determines how many elements are stored between each sample point. A smaller k results in faster random access but uses more memory for the sampling table. See the module-level documentation for a detailed explanation.

Panics

The build method will return an error if k is 0.

pub fn codec(self, codec_spec: Codec) -> Self

Sets the compression codec to use.

The choice of codec can significantly impact the compression ratio. By default, this is Codec::Auto, which analyzes the data to select the best codec.

pub fn build(self, input: &[T]) -> Result<VarVec<T, E, Vec<u64>>, VarVecError>

where BufBitWriter<E, MemWordWriterVec<u64, Vec<u64>>>: BitWrite<E, Error = Infallible> + CodesWrite<E>,

Builds the VarVec from a slice of data, consuming the builder.

This method performs the compression and builds the sampling table.

Errors

Returns an VarVecError if the parameters are invalid (e.g., k=0) or if an error occurs during compression.

Examples

use compressed_intvec::variable::{VarVec, SVarVec, Codec};

let data: &[i16] = &[-100, 0, 50, -2, 1000];

let vec: SVarVec<i16> = VarVec::builder()
    .k(2) // Smaller `k` for faster access
    .codec(Codec::Delta) // Explicitly choose Delta coding
    .build(data)?;

assert_eq!(vec.len(), 5);
assert_eq!(vec.get(0), Some(-100));

Trait Implementations

impl<T: Debug + Storable, E: Debug + Endianness> Debug for VarVecBuilder<T, E>

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

Formats the value using the given formatter.