From 38cc6452530d3083b24882c2a881691feb1cbaa8 Mon Sep 17 00:00:00 2001
From: VedantDave <vedant.dave@unileoben.ac.at>
Date: Mon, 27 Mar 2023 19:22:17 +0200
Subject: [PATCH] Update models to give distribution as well in the output

---
 DPI/models.py | 29 ++++++++++++++++-------------
 1 file changed, 16 insertions(+), 13 deletions(-)

diff --git a/DPI/models.py b/DPI/models.py
index d05e7ec..6d6b6c0 100644
--- a/DPI/models.py
+++ b/DPI/models.py
@@ -34,12 +34,22 @@ class ObservationEncoder(nn.Module):
         std = torch.clamp(std, min=0.0, max=1e5)
 
         # Normal Distribution
+        dist = self.get_dist(mean, std)
+
+        # Sampling via reparameterization Trick
         x = self.reparameterize(mean, std)
-        return x
+
+        encoded_output = {"sample": x, "distribution": dist}
+        return encoded_output
     
     def reparameterize(self, mu, std):
         eps = torch.randn_like(std)
         return mu + eps * std
+    
+    def get_dist(self, mean, std):
+        distribution = torch.distributions.Normal(mean, std)
+        distribution = torch.distributions.independent.Independent(distribution, 1)
+        return distribution
 
 
 class ObservationDecoder(nn.Module):
@@ -114,8 +124,12 @@ class TransitionModel(nn.Module):
         state_prior_mean, state_prior_std = torch.chunk(state_prior, 2, dim=-1)
         state_prior_std = F.softplus(state_prior_std)
 
+        # Normal Distribution
+        state_prior_dist = self.get_dist(state_prior_mean, state_prior_std)
+
+        # Sampling via reparameterization Trick
         sample_state_prior = self.reparemeterize(state_prior_mean, state_prior_std)
-        prior = {"mean": state_prior_mean, "std": state_prior_std, "sample": sample_state_prior, "history": history}
+        prior = {"mean": state_prior_mean, "std": state_prior_std, "sample": sample_state_prior, "history": history, "distribution": state_prior_dist}
         return prior
     
     def reparemeterize(self, mean, std):
@@ -154,15 +168,4 @@ class CLUBSample(nn.Module):  # Sampled version of the CLUB estimator
 
     def forward(self, x_samples, y_samples):
         mu, logvar = self.get_mu_logvar(x_samples)
-        
-        sample_size = x_samples.shape[0]
-        #random_index = torch.randint(sample_size, (sample_size,)).long()
-        random_index = torch.randperm(sample_size).long()
-        
-        positive = - (mu - y_samples)**2 / logvar.exp()
-        negative = - (mu - y_samples[random_index])**2 / logvar.exp()
-        upper_bound = (positive.sum(dim = -1) - negative.sum(dim = -1)).mean()
-        return upper_bound/2.
-
-    def learning_loss(self, x_samples, y_samples):
         return - self.loglikeli(x_samples, y_samples)
\ No newline at end of file