How about a name more mnemonic about indices?
Like
find_index, list_index, or locate_index
Of course, the actual function could actually find many indices for various
predicates.
A user could always make an alias for him or herself if the name is too long.
-sen
On Thu, 4 Jan 2007, Robert Dodier wrote:
> On 1/3/07, sen1 at math.msu.edu <sen1 at math.msu.edu> wrote:
>
>> Given a list, say xx: [2,1,3,3,5], how would I use 'sublist' to
>> extract the indices where '3' occurs?
>
> I think this is a general problem and Maxima should have a built-in
> function for it. How about if we call it "find".
>
> Here's an attempt which worked OK for the one example I tried:
> find (L, p) := block ([I : makelist (i, i, 1, length (L))], sublist
> (I, lambda ([i], is(p(L[i])))));
>
> xx: [2,1,3,3,5];
> P(x) := x=3;
> find (xx, P);
> => [3, 4]
> find (xx, lambda ([x], x=3));
> => [3, 4]
>
> Of course we would want to rewrite it in Lisp.
>
> All the best,
> Robert
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>
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