Re: [Maxima-discuss] How do I get the keys of a hash table in Maxima?

[Eduardo O. <edu...@gm...>]

Oops, I missed that! Thanks!

  myhash : make_array(hashed);
  myhash[42] : 420;
  myhash[ab] : "abab";
  myhash[42];                 /* 420 */
  myhash[ab];                 /* "abab" */
  myhash[cd];                 /* false */
  rest(arrayinfo(myhash),2);  /* [42, ab] */

Cheers,
  E. =)

On Fri, 14 Nov 2025 at 09:39, Stavros Macrakis <mac...@gm...> wrote:

> *arrayinfo*
>
> But that's pretty ugly. We should really have an easy way of iterating
> over a hasharray.
>
>
> On Fri, Nov 14, 2025, 02:22 Eduardo Ochs <edu...@gm...> wrote:
>
>> Hi list,
>>
>> how do I get the keys of a hash table in Maxima?
>> Or, more concretely, if we run this,
>>
>>   myhash : make_array(hashed);
>>   myhash[42] : 420;
>>   myhash[ab] : "abab";
>>   myhash[42];           /* 420 */
>>   myhash[ab];           /* "abab" */
>>   myhash[cd];           /* false */
>>   to_lisp();
>>     (loop for k being the hash-keys in #$myhash$
>>           collect k)
>>     (loop for k being the hash-keys in #$myhash$
>>           if (not (eq k 'dim1))
>>           collect k)
>>     (to-maxima)
>>
>> The first LOOP returns (DIM1 42 $AB) and the second one
>> returns (42 $AB)... but is there a standard way to get
>> something like the result of the second loop without using
>> Lisp?
>>
>> Some links:
>>
>> (info "(maxima)make_array")
>>
>> https://maxima.sourceforge.io/docs/manual/Data-Types-and-Structures.html#index-make_005farray
>> https://sourceforge.net/p/maxima/code/ci/master/tree/src/ar.lisp
>>
>> Thanks in advance!
>>   Eduardo Ochs
>>   https://anggtwu.net/eev-maxima.html
>>
>> _______________________________________________
>> Maxima-discuss mailing list
>> Max...@li...
>> https://lists.sourceforge.net/lists/listinfo/maxima-discuss
>>
>