A=matrix(QQ,([2,-1,0],[-1,2,-1],[-1,2,-1],[-1,2,0]))
print A
b= vector([0,0,0,5])
c=A.auguent(b.transpose())
print
print c.echelon_form()
c.pivot_rows()

Strang-1.3-25-U (last edited 2010-12-17 09:49:22 by jyothi)