class

CosBackward

CosBackward

Autograd node for element-wise cosine $y = \cos(x)$ .

Saves the input x so the backward pass can compute $-\sin(x)$ and scale the upstream gradient by it. The input is interpreted in radians.

Math

\frac{\partial y}{\partial x} = -\sin(x), \qquad \frac{\partial \mathcal{L}}{\partial x} = -\sin(x)\,\frac{\partial \mathcal{L}}{\partial y}.$$

schema_v1OpSchema

Registered as "cos" with AmpPolicy::Promote.

Dispatch: Accelerate vvcosf/vvcos (CPU) / MLX cos (GPU).

Static methods

static

int dispatch(backend::IBackend & be, const int & a, const int & s, Dtype dt)

Forward — calls IBackend::cos to compute $y = \cos x$ .

int grad_formula(const int & g)

Backward — $\partial y/\partial x = -\sin x$ , scaled by grad_out.