02610

02610/Week 13/genA.m

+function A = genA(tau)
+
+if tau<=0 || tau>=1
+    error('tau need be in (0,1)!');
+end
+
+n = 500;
+A = speye(n);
+
+rng(100);
+R = rand(n)*2-1;
+R = R-diag(diag(R));
+
+A = A+R;
+A = (A+A')/2;
+
+Ind = abs(A)>tau;
+A(Ind) = 0;
+A = A+speye(n);