Please explain to me the difference in the two computations:
lin=2*x - y + 2.0;lin(x=-11/9,y=-4/9)
-2.22044604925031e-16
and
2*(-11/9)-(-4/9)+2.000000000000000000
0.000000000000000000
It has to be a floating point computation, and I'm interested only in the sign of the outcome, which is why the first example gives me trouble.