Struct BlockQ2K 

#[repr(C)]
pub struct BlockQ2K {
    pub scales: [u8; 16],
    pub qs: [u8; 64],
    pub d: f16,
    pub dmin: f16,
}

Q2_K super-block: 256 weights quantized to 2 bits each.

Layout (84 bytes):

• scales: 16 bytes — packed 4-bit scale/min pairs for 16 sub-blocks of 16 weights. Each byte holds two 4-bit values: low nibble = scale, high nibble = min.
• qs: 64 bytes — 256 x 2-bit quantized weights (4 per byte, LSB first).
• d: FP16 super-block scale.
• dmin: FP16 super-block minimum.

Dequant: w[i] = d * sub_scale * q[i] - dmin * sub_min

Fields

scales: [u8; 16]

Packed 4-bit scale/min pairs for 16 sub-blocks.

qs: [u8; 64]

256 x 2-bit quantized weights, 4 per byte.

d: f16

Super-block scale (FP16).

dmin: f16

Super-block minimum (FP16).

Implementations

impl BlockQ2K

pub fn dequant(blocks: &[Self], output: &mut [f32]) -> BonsaiResult<()>

Dequantize a slice of Q2_K blocks into f32 output.

output must have length blocks.len() * QK_K.

pub fn quantize(input: &[f32]) -> BonsaiResult<Vec<Self>>

Quantize f32 input into Q2_K blocks.

Input length must be a multiple of QK_K (256).

pub fn dequant_row_to_buf(blocks_for_row: &[Self], buf: &mut Vec<f32>)

Dequantize a single row’s worth of Q2_K blocks into a pre-allocated buffer.

buf will be extended by blocks_for_row.len() * 256 elements.

pub fn slice_from_bytes(data: &[u8]) -> BonsaiResult<&[Self]>

Zero-copy cast of a byte slice to a slice of BlockQ2K.

Returns error if length is not a multiple of BLOCK_Q2_K_BYTES (84) or if the pointer is not properly aligned.

Trait Implementations

impl Clone for BlockQ2K

fn clone(&self) -> BlockQ2K

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for BlockQ2K

impl Debug for BlockQ2K

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

Formats the value using the given formatter.

impl PartialEq for BlockQ2K

fn eq(&self, other: &BlockQ2K) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for BlockQ2K