concision_linear/norm/layer/
mod.rs1pub(crate) use self::utils::*;
9pub use self::{config::*, model::*};
10
11pub(crate) mod config;
12pub(crate) mod model;
13
14pub const EPSILON: f64 = 1e-5;
15
16pub(crate) mod prelude {
17 pub use super::config::Config as LayerNormConfig;
18 pub use super::model::LayerNorm;
19}
20
21pub(crate) mod utils {
22 use nd::prelude::*;
23 use nd::{Data, RemoveAxis};
24 use num::traits::{Float, FromPrimitive};
25
26 pub(crate) fn layer_norm<A, S, D>(x: &ArrayBase<S, D>, eps: f64) -> Array<A, D>
27 where
28 A: Float + FromPrimitive,
29 D: Dimension,
30 S: Data<Elem = A>,
31 {
32 let mean = x.mean().unwrap();
33 let denom = {
34 let eps = A::from(eps).unwrap();
35 let var = x.var(A::zero());
36 (var + eps).sqrt()
37 };
38 x.mapv(|xi| (xi - mean) / denom)
39 }
40
41 pub(crate) fn layer_norm_axis<A, S, D>(x: &ArrayBase<S, D>, axis: Axis, eps: f64) -> Array<A, D>
42 where
43 A: Float + FromPrimitive,
44 D: RemoveAxis,
45 S: Data<Elem = A>,
46 {
47 let eps = A::from(eps).unwrap();
48 let mean = x.mean_axis(axis).unwrap();
49 let var = x.var_axis(axis, A::zero());
50 let inv_std = var.mapv(|v| (v + eps).recip().sqrt());
51 let x_norm = (x - &mean) * &inv_std;
52 x_norm
53 }
54}