cd_hinton_hid_binary: added raoBlackwell, gibbs-sampling

source/Rbm.cpp

@@ -175,20 +175,52 @@ void Rbm::cd_hinton_hid_binary(arma::mat const &v_data, arma::mat &dw, arma::mat
 {
 	// Start positive phase	
 	arma::mat poshidprobs = prob(v_to_h(v_data));
-	arma::mat posprods = v_data.t() * poshidprobs;
+
+	arma::mat posprods;
 	arma::mat poshidact = arma::sum(poshidprobs);
 	arma::mat posvisact = arma::sum(v_data);
 	
 	// End of positive phase
 	arma::mat poshidstates = sample(poshidprobs);
 
-	// Start negative phase	
+	if (m_params.doRaoBlackwell)
-	arma::mat negdata = prob(h_to_v(poshidstates));
+	{
-	arma::mat neghidprobs = prob(v_to_h(negdata)); 
+		posprods = v_data.t() * poshidprobs;
-	arma::mat negprods = negdata.t() * neghidprobs; 
+	}
-	arma::mat neghidact = arma::sum(neghidprobs);
+	else
-	arma::mat negvisact = arma::sum(negdata);
+	{
+		posprods = v_data.t() * sample(poshidprobs);
+	}
 
+	arma::mat negprods;
+	arma::mat neghidact;
+	arma::mat negvisact;
+	for (int i=0; i < m_params.numGibbs; i++)
+	{
+		// Start negative phase	
+		arma::mat negdata = prob(h_to_v(poshidstates));
+		arma::mat neghidprobs;
+		if (m_params.gibbsDoSampleVisible)
+		{
+			neghidprobs = prob(v_to_h(sample(negdata))); 
+		}
+		else
+		{
+			neghidprobs = prob(v_to_h(negdata)); 
+		}
+		negprods = negdata.t() * neghidprobs; 
+		neghidact = arma::sum(neghidprobs);
+		negvisact = arma::sum(negdata);
+
+		if (m_params.gibbsDoSampleHidden)
+		{
+			poshidprobs = sample(neghidprobs);
+		}
+		else
+		{
+			poshidprobs = neghidprobs;
+		}
+	}
 	// Update weight deltas
 	dw = posprods - negprods;
 	dbv = posvisact - negvisact;