Error in acceptance probability?

[mattiasflodin]

Hi,

Are you missing a call to exp() in your acceptance probability function? In the original description by Kirkpatrick et al, (-de / temperature).exp() would be used. In your code, at line 108 of solver.rs, you check whether a random number in range [0, 1) is smaller than -de / temperature. But since we know both de and temperature are positive, -de / temperature must be a negative number and hence the random positive number can never be smaller. In other words, it seems your annealing schedule will never allow the energy to increase.