Struct Rope 

pub struct Rope {
    pub dims: usize,
    pub theta: f64,
    pub neox: bool,
    pub scaling: RopeScaling,
    pub sections: Option<[usize; 4]>,
}

The rotary position embedding.

Fields

dims: usize

How many of each head’s dimensions rotate (the rest pass through).

theta: f64

neox: bool

NEOX pairs dimension i with i + dims/2; the original form pairs 2i with 2i+1.

scaling: RopeScaling

sections: Option<[usize; 4]>

Interleaved multi-section rotation (rope.dimension_sections, Qwen3.5): frequency i reads position stream i mod Σsections as llama.cpp’s IMROPE assigns it. A text token’s streams are [p, p, p, 0], so a frequency assigned to the fourth stream does not turn.

Implementations

impl Rope

pub fn rotation(&self, i: usize, pos: usize, factor: Option<f64>) -> (f64, f64)

(cos, sin) of frequency i at text position pos, each scaled by the rotation’s magnitude, as ggml’s CPU rope computes them (rope_yarn): the angle is pos·θ^(−2i/dims), divided by the checkpoint’s frequency factor factor when it stores one; linear scaling divides it by its factor; YaRN blends the divided and the undivided angle by a ramp over the correction dimensions and scales the pair by its magnitude.

pub fn text_position(&self, i: usize, pos: usize) -> usize

The position frequency i turns by for a text token at pos.

Trait Implementations

impl Clone for Rope

fn clone(&self) -> Rope

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Rope

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

Formats the value using the given formatter.

impl PartialEq for Rope

fn eq(&self, other: &Rope) -> 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 Rope