#To find the incidence matrix and its null-space
print 'The incidence matrix is'
A = matrix([[-1,-1,0,0,-1,0],[1,0,-1,-1,0,0],[0,1,1,0,0,-1],[0,0,0,1,1,1]])
print A
b = A.transpose()
print 'Transpose of the matrix is '
print b