Is it feasible to directly calculate the DSM loss function without scorenet estimation?

[AlyssaYoung]

I saw an implementation of the formula form. I wonder whether it is feasible to directly calculate the loss via torch.autograd operations, if I define an energy function, like the logSumExp function in this paper 'Your classifier is secretly an energy based model and you should treat it like one'.

ncsn/losses/dsm.py

Lines 5 to 15 in 7f27f4a

	def dsm(energy_net, samples, sigma=1):
	samples.requires_grad_(True)
	vector = torch.randn_like(samples) * sigma
	perturbed_inputs = samples + vector
	logp = -energy_net(perturbed_inputs)
	dlogp = sigma ** 2 * autograd.grad(logp.sum(), perturbed_inputs, create_graph=True)[0]
	kernel = vector
	loss = torch.norm(dlogp + kernel, dim=-1) ** 2
	loss = loss.mean() / 2.
	return loss