[ 仅 API 调用方式不一致 ]torch.autograd.Function.forward

torch.autograd.Function.forward(*args, **kwargs)

paddle.autograd.PyLayer.forward(ctx, *args, **kwargs)

# PyTorch 写法
class cus_tanh(torch.autograd.Function):
    @staticmethod
    def forward(ctx, x, func=torch.square):
        ctx.func = func
        y = func(x)
        return y

    @staticmethod
    def backward(ctx, dy):
        grad = dy + 1
        return grad

# Paddle 写法
class cus_tanh(paddle.autograd.PyLayer):
    @staticmethod
    def forward(ctx, x, func=paddle.square):
        ctx.func = func
        y = func(x)
        return y

    @staticmethod
    def backward(ctx, dy):
        grad = dy + 1
        return grad