diff toolboxes/FullBNT-1.0.7/KPMtools/logsum_simple.m @ 0:e9a9cd732c1e tip

first hg version after svn
author wolffd
date Tue, 10 Feb 2015 15:05:51 +0000
parents
children
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolboxes/FullBNT-1.0.7/KPMtools/logsum_simple.m	Tue Feb 10 15:05:51 2015 +0000
@@ -0,0 +1,23 @@
+function result = logsum(logv)
+
+len = length(logv);
+if (len<2);
+  error('Subroutine logsum cannot sum less than 2 terms.');
+end;
+
+% First two terms
+if (logv(2)<logv(1)),
+  result = logv(1) + log( 1 + exp( logv(2)-logv(1) ) );
+else,
+  result = logv(2) + log( 1 + exp( logv(1)-logv(2) ) );
+end;
+
+% Remaining terms
+for (i=3:len),
+  term = logv(i);
+  if (result<term),
+    result = term   + log( 1 + exp( result-term ) );
+  else,
+    result = result + log( 1 + exp( term-result ) );
+  end;    
+end