a = matrix([[26,-2,2],[2,21,4],[4,2,28]])
a
b = a.eigenvalues()
b
c = []
sum = 0
for i in range(len(b)):
      c.append(b[i]^2)
      sum = sum + c[i]
print sum

Strang-18.7 -4 (last edited 2010-12-17 12:10:32 by prasad)