Question: will this difference in result from the same command influence up and down in quantum computation?

with(LinearAlgebra):
test1 := Matrix([[1,-1],[-1,1]]);
for i from 1 to 20 do
print(Eigenvectors(test1)[2]);
od:

i run the same command 20 times, but sometimes left has negative 1 , sometimes right has negative 1

why position is like random , is my maple has virus?

the result are not consistent, i am learning quantum computation, will this influence the quantum computation and result?

i am doing up and down and change to a differential equation, Pauli equation

It seems only one Pauli equation

i find 3*3 matrix 

has 3 different kinds of matrix

one is row 1 and row 2

second is row 1 and row 3

Third is row 2 and 3

column 1 is constant 

Is there any one has the same experience to predict these 3 kind of matrix, and know what I mentioned?