uhm, Octave if I'm not mistaken. it had some usefull built in stuff for Matrices and such, but the language itself was just weird, it wasn't bad, it just felt... wrong (I can't remember why, probably stuff like 1 based arrays and stuff like that)

I believe "some" breaks on the first hit, where as "every" has to go over every element in the array, making it a lot slower for higher numbers. (not sure if this is the case with javascript, but it would make sense)

it clearly states what is expected, if you want your code to return 0 for fib(n = 0) just start off with an n--....

a fun expansion would be to be send directly to the next part (after completing this kata) where you get to implement the gradient descent algorithm,
I've done this once for a CS course, and at the time didn't understand it too well (+ it was in a weird language I barely understood), it would be fun to do in JS (I think)

as this kata stands now, it's a fun introduction, but it doesn't really teach anything about machine learning :/

1: define in your instructions that a non integer time can be given, I was designing the whole thing around integer times and caching states in case of instance time 10 being requested and then time 2 is requested, I'll just return what I previously calculated for time 2, same goes for from 2 to 10, I start off at the latest time state (in that case 2) and continue it to 10, this approach doesn;t work with non integer times (or at least not so well)

2: please define how the mass of the ship is taken into the equation, form the test that is given I can deduce that a force of 1, fora duration of 1, with a mass of 1 results in a difference in location of 0.5, where's this 0.5 comming from? should I devide the event force by 1 + the mass of my ship? I'm just guessing here :/

and 3 (but this is not your fault): syntax errors need line numbers... (I've got a unexpected '{' error and can;t find any problem with my code :/
(I'll post my current code in a different comment and flag it as a spoiler if you'd like to take a look)

the iterator function wants the index of the value as its 2nd parameter I believe.

I find that he clearly defined the way your function should work. It might not have been the general convention, but it was clear enough to not matter one bit, if you want to work with a zero based index you can just take the input and give it a "--"...

ah crap, well that makes things harder, I just ignored all white space....

it would have helped A LOT if the description dais the namespace is already defined and should not be overwritten entirely....