lucid.sin

lucid.sin(a: Tensor, /) Tensor

The sin function computes the element-wise sine of each element in the input tensor.

Function Signature

def sin(a: Tensor) -> Tensor

Parameters

  • a (Tensor): The input tensor for which the sine is computed.

Returns

  • Tensor:

    A new tensor containing the element-wise sine of the input tensor. If a requires gradients, the resulting tensor will also require gradients.

Forward Calculation

The forward calculation for sin is:

\[\mathbf{out}_i = \sin(\mathbf{a}_i)\]

where \(\mathbf{a}_i\) is the element of the input tensor a, and \(\mathbf{out}_i\) is the corresponding element of the output tensor.

Backward Gradient Calculation

For a tensor a involved in the sin operation, the gradient with respect to the output (out) is computed as:

\[\frac{\partial \mathbf{out}_i}{\partial \mathbf{a}_i} = \cos(\mathbf{a}_i)\]

This means that for each element in the input tensor, the gradient is the cosine of the corresponding value in the tensor.

Example

>>> import lucid
>>> a = Tensor([0, math.pi / 2, math.pi], requires_grad=True)
>>> out = lucid.sin(a)
>>> print(out)
Tensor([0.         1.         0.        ], grad=None)

The sin function supports tensors of arbitrary shape:

>>> import lucid
>>> a = Tensor([[0, math.pi / 4], [math.pi / 2, math.pi]], requires_grad=True)
>>> out = lucid.sin(a)
>>> print(out)
Tensor([[0.         0.70710678] [1.         0.        ]], grad=None)