Mercurial > hg > camir-aes2014

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

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first hg version after svn
author wolffd
date Tue, 10 Feb 2015 15:05:51 +0000
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolboxes/FullBNT-1.0.7/KPMtools/is_psd.m	Tue Feb 10 15:05:51 2015 +0000
@@ -0,0 +1,11 @@
+function b = positive_semidefinite(M)
+%
+% Return true iff v M v' >= 0 for any vector v.
+% We do this by checking that all the eigenvalues are non-negative.
+
+E = eig(M);
+if length(find(E>=0)) == length(E)
+  b = 1;
+else
+  b = 0;
+end