H=rand(5) H = 0.9501 0.7621 0.6154 0.4057 0.0579 0.2311 0.4565 0.7919 0.9355 0.3529 0.6068 0.0185 0.9218 0.9169 0.8132 0.4860 0.8214 0.7382 0.4103 0.0099 0.8913 0.4447 0.1763 0.8936 0.1389 L=eig(H) L = 2.8043 -0.0490 + 0.5617i -0.0490 - 0.5617i -0.0381 0.2093 H=0.5*(H+H'); L=eig(H) L = 0.3019 0.4521 -0.5469 -0.1703 2.8408 M(1)=det(H(1:1,1:1)); M(2)=det(H(1:2,1:2)); M(3)=det(H(1:3,1:3)); M(4)=det(H(1:4,1:4)); M(5)=det(H(1:5,1:5)); M M = 0.9501 0.1871 0.0919 -0.1886 0.0361 H=rand(5) H = 0.2028 0.0153 0.4186 0.8381 0.5028 0.1987 0.7468 0.8462 0.0196 0.7095 0.6038 0.4451 0.5252 0.6813 0.4289 0.2722 0.9318 0.2026 0.3795 0.3046 0.1988 0.4660 0.6721 0.8318 0.1897 H=0.5*(H+H'); L=eig(H) L = 0.4073 -0.0007 -0.3116 -0.4257 2.3745 H=H+0.5*eye(5) H = 0.7028 0.1070 0.5112 0.5552 0.3508 0.1070 1.2468 0.6457 0.4757 0.5877 0.5112 0.6457 1.0252 0.4420 0.5505 0.5552 0.4757 0.4420 0.8795 0.5682 0.3508 0.5877 0.5505 0.5682 0.6897 L=eig(H) L = 0.9073 0.4993 0.1884 0.0743 2.8745 M(1)=det(H(1:1,1:1)); M(2)=det(H(1:2,1:2)); M(3)=det(H(1:3,1:3)); M(4)=det(H(1:4,1:4)); M(5)=det(H(1:5,1:5)); M M = 0.7028 0.8647 0.3383 0.0896 0.0182 H=H-3*eye(5) H = -2.2972 0.1070 0.5112 0.5552 0.3508 0.1070 -1.7532 0.6457 0.4757 0.5877 0.5112 0.6457 -1.9748 0.4420 0.5505 0.5552 0.4757 0.4420 -2.1205 0.5682 0.3508 0.5877 0.5505 0.5682 -2.3103 L=eig(H) L = -2.0927 -2.5007 -2.8116 -2.9257 -0.1255 M(1)=det(H(1:1,1:1)); M(2)=det(H(1:2,1:2)); M(3)=det(H(1:3,1:3)); M(4)=det(H(1:4,1:4)); M(5)=det(H(1:5,1:5)); M M = -2.2972 4.0161 -6.4447 9.5691 -5.4025 eig([2 1;1 0]) ans = 2.4142 -0.4142