Question

I just noticed that when I change the last line in the code fragment from potential =+ rep_pot to potential = potential + rep_pot, I get completely different behaviour. Has anybody got any idea why this is happening?

double potential = euclideanDistance(i, goal);
for (IntPoint h: hits){
    double dist = euclideanDistance(i, h);
    double a = range - dist;
    double rep_pot = (Math.exp(-1/a)) / dist;
    potential =+ rep_pot;
}

Answer 1

Yes, because these two things are not equivalent.

potential =+ rep_pot;

Here we have potential assigned a value of the expression ‘unary plus rep_pot’

The thing you intendet to write looks differently:

potential += rep_pot;

And this is equivalent to

potential = potential + rep_pot;