function [] = prob_10_15
% PROB_10_15 - 
% 
% Written by:
% -- 
% John L. Weatherwax                2005-08-28
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
%-----

phi = 1.61803399;

h=sqrt(2-2*cos(2*pi/30));
A=ret_mat_A(h);
e = eig( A );
abs(e(1)), abs(e(2))
circlegen;

h=1/phi;
A=ret_mat_A(h);
e = eig( A );
abs(e(1)), abs(e(2))
circlegen(1/phi);

h=phi;
A=ret_mat_A(h);
e = eig( A );
abs(e(1)), abs(e(2))
circlegen(phi);

h=1.4140;
A=ret_mat_A(h);
e = eig( A );
abs(e(1)), abs(e(2))
circlegen(h); 

h=sqrt(2); 
A=ret_mat_A(h);
e = eig( A );
abs(e(1)), abs(e(2))
circlegen(sqrt(2)); 

h=1.4144;
A=ret_mat_A(h);
e = eig( A );
abs(e(1)), abs(e(2))
circlegen(1.4144); 

circlegen(1.5); 

h=2;
A=ret_mat_A(h);
e = eig( A );
abs(e(1)), abs(e(2))
circlegen(2); 

h=2.5;
A=ret_mat_A(h);
e = eig( A );
abs(e(1)), abs(e(2))
circlegen(2.5);