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"""pytorch utils for VAEs."""
import torch
[docs]def reparameterize(mu: torch.Tensor, logvar: torch.Tensor) -> torch.Tensor:
"""
Applies reparametrization trick to obtain sample from latent space.
Args:
mu: the latent means of shape batch_size x latent_size.
logvar: latent log variances, shape batch_size x latent_size.
Returns:
torch.Tensor: sampled Z from the latent distribution.
"""
return torch.randn_like(mu).mul_(torch.exp(0.5 * logvar)).add_(mu) # type:ignore