You cannot multiply a 1x2 matrix by a 1x2 matrix. To calculate the point product between their lines, the second must be transposed.
from scipy import linalg, mat, dot
a = mat([-0.711,0.730])
b = mat([-1.099,0.124])
c = dot(a,b.T)/linalg.norm(a)/linalg.norm(b)
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