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I'd like to know if it is possible to use NestList on a regular function of several arguments, such as:

fc[x_, y_] := {x + y, x - y};
res = NestList[ fc[x,y], {100, 75}, 50]

I just started learning Mathematica at my university, read about pure functions, but from the homework's text it doesn't look like I should use that. Roughly translated, it would be "Define a function of 2 arguments (...) and apply NestList on this function."

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  • $\begingroup$ I discussed a similar example here,may possibly be relevant as another illustration. $\endgroup$
    – Leonid Shifrin
    Oct 1, 2012 at 20:35

2 Answers 2

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One way to deal with "multiple inputs" to a function like NestList is to express the many inputs as a single vector. For example:

f[{x_, y_}] := {x + y, x - y};
NestList[f, {100, 75}, 5]

does what you are looking for

{{100, 75}, {175, 25}, {200, 150}, {350, 50}, {400, 300}, {700, 100}}
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  • $\begingroup$ I didn't know I could specify arguments of the function in such manner. Neat. Thank you $\endgroup$
    – Martin Melka
    Oct 1, 2012 at 20:19
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I suggest to look at this :

fc[x_, y_] := {x + y, x - y}
NestList[fc @@ # &, {100, 75}, 5]

{{100, 75}, {175, 25}, {200, 150}, {350, 50}, {400, 300}, {700, 100}}

First, after SetDelayed (:=) you don't have to use ;, look at CompoundExpression. Second, fc has to be applied (Apply) to the list of arguments.

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