From 6c340dcefd0e8761e3fbdc530ac23091100fdb8c Mon Sep 17 00:00:00 2001
From: David Nolte <nolte@purdue.edu>
Date: Mon, 1 Feb 2021 11:02:34 -0500
Subject: [PATCH] Create eigenlap.m

---
 eigenlap.m | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 eigenlap.m

diff --git a/eigenlap.m b/eigenlap.m
new file mode 100644
index 0000000..f5f421a
--- /dev/null
+++ b/eigenlap.m
@@ -0,0 +1,27 @@
+% function [synch,l2,lmax,spec] = eigenlap(node)
+% Calculates the eigenvalues 2 and N
+% synch = ratio l2/lmax gives measure of synchronizabity
+% spec is the full spectrum
+
+
+function [synch,l2,lmax,spec] = eigenlap(node)
+
+[A,degree,Lap] = adjacency(node);
+
+[dum,N] = size(Lap);
+l = eig(Lap);
+spec = l;
+
+flag = 0; ind = 1;
+while flag == 0
+    ind = ind + 1;
+    l2tmp = min(l(ind:N));
+    if l2tmp > 1/sqrt(N)
+        l2 = l2tmp;
+        flag = 1;
+    end
+end
+        
+
+lmax = l(N);
+synch = lmax/l2;