Well defining the vector like this worked,
Code:
my_pos = my.x;
crowd_pos[0] = my_pos;

But then when I try a comparison, like so
Code:
if(vec_dist(my.x, crowd_pos[0]) < 10)

It crashes. I know I'm comparing two of the same vectors; my.x and crowd_pos[0] are the same, but if do this,
Code:
my_pos = vector(0,0,0);

And compare them it still crashes.