How many eigenvalues of a random
matrix are real?
>> e=eig(randn(7))
e =
1.9771
1.3442
0.6316
-1.1664
+ 1.3504i
-1.1664
- 1.3504i
-2.1461
+ 0.7288i
-2.1461
- 0.7288i
3 real
1 real
5 real
7x7 random Gaussian