Re: Elisp function that performs numeric computations

[Sergey Organov]

Emanuel Berg via Users list for the GNU Emacs text editor
<help-gnu-emacs@gnu.org> writes:

> fatiparty--- via Users list for the GNU Emacs text editor wrote:
>
>>>>>> "Compute depth to use."
>>>>>>  (interactive)
>>>>>>  
>>>>>>  (let* ( (j rptdepth)
>>>>>>  (w (- maxdepth j))
>>>>>>  (p (+ w 1))
>>>>>>  (r (mod (- depth maxdepth 1) p) )
>>>>>>  (o (+ j r)) )
>>>>>>  o))
>>>>>>
>>>>
>>>> I would like to adapt the function a little bit more. If
>>>> depth <= maxdepth I want to set o=depth instead of
>>>> performing the computation shown for the variable o.
>>>>
>>>
>>> Did I get it right, I wonder?
>>>
>>> (defun test (depth maxdepth rptdepth)
>>>  (if (<= depth maxdepth)
>>>  depth
>>>  (+ rptdepth
>>>  (mod (- depth maxdepth 1)
>>>  (- maxdepth rptdepth -1)))))
>>>
>>> Is it how true (E)Lisp'er would write it?
>>>
>>
>> What you have done is good. But although you have got to
>> a simple solution, I want to code the more complicated
>> solution for the case where let* is involved (within which
>> local variables are defined).
>
> The reason there is no `let' (or `let*') in his code is
> because there is no repitition of computation patterns ...
>
> As for "Is it how true (E)Lisp'er would write it?" I'd write
> it, whatever it is, like this:
>
> (defun organov (dep top rep)
>   (if (<= dep top)
>       dep
>     (+ rep
>        (mod (1- (- dep top))
>             (1+ (- top rep)) ))))

Nice, thanks! Didn't know me could be cut to such a brief definition
though :)

-- Sergey Organov