meuron 0.4.0

Meuron is a modular neural network library written in rust for training simple neural networks.
Documentation 
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// Softmax backward (vector-Jacobian product).
@group(0) @binding(0) var<storage, read>       z    : array<f32>;
@group(0) @binding(1) var<storage, read>       grad : array<f32>;
@group(0) @binding(2) var<storage, read_write> out  : array<f32>;

struct Dims { batch: u32, last_dim: u32, pad0: u32, pad1: u32 }
@group(0) @binding(3) var<uniform> d: Dims;

@compute @workgroup_size(256)
fn main(@builtin(global_invocation_id) gid: vec3<u32>) {
    let b = gid.x;
    if b >= d.batch { return; }
    let off = b * d.last_dim;

    var mx = z[off];
    for (var i = 1u; i < d.last_dim; i++) {
        if z[off + i] > mx { mx = z[off + i]; }
    }
    var s: f32 = 0.0;
    for (var i = 0u; i < d.last_dim; i++) {
        s = s + exp(z[off + i] - mx);
    }
    var dot: f32 = 0.0;
    for (var i = 0u; i < d.last_dim; i++) {
        dot = dot + (exp(z[off + i] - mx) / s) * grad[off + i];
    }
    for (var i = 0u; i < d.last_dim; i++) {
        out[off + i] = (exp(z[off + i] - mx) / s) * (grad[off + i] - dot);
    }
}