>>So, a particle will exchange its velocity (dx, dy, dz) with every other particle. That means that when you finish one cycle of exchanges, a particle will retain the velocity of the last particle it happened to interact with. The order of the interaction can make quite a difference, then. I would say, the FOR EACH doesn't give you a very fine control over the order in which the particles interact. Perhaps you should use an array to have a better control over this order of exchanges.
>
>
>Hmmm.
>
>Shouldn't
>
>FOR EACH xxx IN myarray
>
>be exactly equal to
>
>FOR nnn = 1 to alen(myarray)
> xxxx = myarray[nnn]
>
>?
It should do the same, except for the order - and in this case, the order of evaluation seems to be important. I believe that with a
for each, you have no way of controlling the order.
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