diff toolboxes/FullBNT-1.0.7/bnt/general/unroll_dbn_topology.m @ 0:e9a9cd732c1e tip

first hg version after svn

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolboxes/FullBNT-1.0.7/bnt/general/unroll_dbn_topology.m	Tue Feb 10 15:05:51 2015 +0000
@@ -0,0 +1,28 @@
+function M = unroll_dbn_topology(intra, inter, T, intra1)
+% UNROLL_DBN_TOPOLOGY Make the block diagonal adjacency matrix for a DBN consisting of T slices
+% M = unroll_dbn_topology(intra, inter, T, intra1)
+%
+% intra is the connectivity within a slice, inter between two slices.
+% M will have intra along the diagonal, and inter one above the diagonal.
+% intra1 is an optional argumnet, in case the intra is different for the first slice.
+
+if nargin < 4, intra1 = intra; end
+
+ss = length(intra); % slice size
+M = sparse(ss*T, ss*T);
+
+b = 1:ss;
+M(b,b) = intra1;
+M(b,b+ss) = inter;
+
+for t=2:T-1
+  b = (1:ss) + (t-1)*ss;
+  M(b,b) = intra;
+  M(b,b+ss) = inter;
+end
+
+t = T;
+b = (1:ss) + (t-1)*ss;
+M(b,b) = intra;
+
+