numpy 线性方程组求解、矩阵数乘、矩阵乘法、逆矩阵、方阵LU分解
代码如下：
# 3x + y = 9
# x + 2y = 8
import numpy as np
import scipy as scipy
from scipy import linalg
a = np.array([[3,1],[1,2]])
b = np.array([9,8])
result = np.linalg.solve(a,b)
print result
A = np.array([[1,2,3],
[4,5,7],
[7,8,9]])
I = np.eye(3)
print A
print I
print 3*A
print A+I
print A.T
print np.dot(A, I)
print np.linalg.inv(A)
A = np.array([[1,2,3],
[4,5,7],
[7,8,9]])
l,u = scipy.linalg.lu(A,True)
print 'l=========='
print l
print 'u=========='
print u
print 
