Operación con matrices usando Sympy-Python

isra@linuxmint ~ $ python
Python 2.7.4 (default, Sep 26 2013, 03:20:56) 
[GCC 4.7.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from sympy import Matrix
>>> Matrix([[1,2,3],[4,6,7]])
[1, 2, 3]
[4, 6, 7]
>>> A=Matrix([[1,2,3],[4,6,7]])
>>> b=3
>>> c = b*A
>>> c
[ 3,  6,  9]
[12, 18, 21]
>>> 
>>> x=Symbol('x')
>>> y=Symbol('y')
>>> H = Matrix([[x+y,4],[3,x-y]])
>>> H
[x + y,     4]
[    3, x - y]
>>> h = H*H
>>> h
[(x + y)**2 + 12,             8*x]
[            6*x, (x - y)**2 + 12]
>>> #matris identidad
... 
>>> eye(4)
[1, 0, 0, 0]
[0, 1, 0, 0]
[0, 0, 1, 0]
[0, 0, 0, 1]
>>> #matris ceros
... 
>>> zeros(4)
[0, 0, 0, 0]
[0, 0, 0, 0]
[0, 0, 0, 0]
[0, 0, 0, 0]
>>> #matris unos
... 
>>> ones(5,6)
[1, 1, 1, 1, 1, 1]
[1, 1, 1, 1, 1, 1]
[1, 1, 1, 1, 1, 1]
[1, 1, 1, 1, 1, 1]
[1, 1, 1, 1, 1, 1]
>>> v1 = Matrix([1,2,3])
>>> v2 = Matrix([5,7,8])
>>> v3 = v1.cross(v2)
>>> v3
[-5, 7, -3]
>>> #producto punto
... 
>>> v4 = v1.dot(v2)
>>> v4
43