How do you write this in lisp



Try my new code and compile simpbetween.

On Tue, Apr 6, 2010 at 11:38, Richard Hennessy <rich.hennessy at verizon.net>wrote:

> I would like between to be as fast a signum.  Probably not likely to happen
> I guess.
>
>
> Rich
>
> --------------------------------------------------
> From: "Richard Hennessy" <rich.hennessy at verizon.net>
> Sent: Tuesday, April 06, 2010 11:32 AM
> To: "Stavros Macrakis" <macrakis at alum.mit.edu>; "Barton Willis" <
> willisb at unk.edu>; "Maxima List" <maxima at math.utexas.edu>
>
> Subject: Re: [Maxima] How do you write this in lisp
>
>  Here is a better way to compare speed.  These two expressions are
>> equivalent.
>>
>> (%i3) for i : 1 thru 100 do for j : 1 thru 100 do
>> (signum(x-i)-signum(x-j))/2;
>> Evaluation took 3.3300 seconds (3.3300 elapsed)
>> (out3)
>>           done
>> (%i4) for i : 1 thru 100 do for j : 1 thru 100 do between(x,i,j);
>> Evaluation took 19.0600 seconds (19.0600 elapsed)
>> (out4)
>>           done
>>
>> --------------------------------------------------
>> From: "Stavros Macrakis" <macrakis at alum.mit.edu>
>> Sent: Monday, April 05, 2010 11:13 PM
>> To: "Richard Hennessy" <rich.hennessy at verizon.net>; "Barton Willis" <
>> willisb at unk.edu>; "Maxima List" <maxima at math.utexas.edu>
>> Subject: Re: [Maxima] How do you write this in lisp
>>
>>  Well, it will depend on how often the conditions are true or false. If
>>> that's the issue, you can set compbx only on demand.
>>>
>>> How are you measuring speed?
>>>
>>>         -s
>>>
>>> On 2010-04-05, Richard Hennessy <rich.hennessy at verizon.net> wrote:
>>>
>>>> Hi,
>>>>
>>>> Actually this was a bad idea.  I tried making between a regular function
>>>> and
>>>> it breaks a lot of code that I have
>>>> written.  It has to be a simplifying function or I can't integrate
>>>> expressions that contain it.
>>>>
>>>> I have posted the newest pw.mac at my site.  It can use between or
>>>> signum.
>>>> I have to update the help now.  You can get
>>>> it here.  http://mysite.verizon.net/res11w2yb/pw.mac.txt  BTW I have
>>>> tried
>>>> using sign() in the definition of simpbetween
>>>> but it is slower that using the relational operators.  Maybe I am going
>>>> about it the right way.
>>>>
>>>> Rich
>>>>
>>>>
>>>> --------------------------------------------------
>>>> From: "Richard Hennessy" <rich.hennessy at verizon.net>
>>>> Sent: Monday, April 05, 2010 10:05 PM
>>>> To: "Barton Willis" <willisb at unk.edu>; <macrakis at alum.mit.edu>
>>>> Cc: "Maxima List" <maxima at math.utexas.edu>
>>>> Subject: Re: [Maxima] How do you write this in lisp
>>>>
>>>>  "simplification--how much is too much".
>>>>>
>>>>> Maybe between should not be a simplifying function at all.  I could
>>>>> make
>>>>> the body of simpbetween with some possibly
>>>>> necessary changes the body of a regular user function called between.
>>>>>  I
>>>>> am not sure I like simplifying functions that
>>>>> much.  Maybe that would work out better.  I can't make up my mind on
>>>>> this
>>>>> yet.  I am going to try experimenting with
>>>>> both ways
>>>>> of doing it.
>>>>>
>>>>> Rich
>>>>>
>>>>>
>>>>> --------------------------------------------------
>>>>> From: "Barton Willis" <willisb at unk.edu>
>>>>> Sent: Monday, April 05, 2010 9:17 PM
>>>>> To: <macrakis at alum.mit.edu>
>>>>> Cc: "Richard Hennessy" <rich.hennessy at verizon.net>; "Maxima List"
>>>>> <maxima at math.utexas.edu>
>>>>> Subject: Re: [Maxima] How do you write this in lisp
>>>>>
>>>>>  It would be great if there was a definitive guide to writing
>>>>>> simplifying
>>>>>> functions.
>>>>>> There are plenty of examples, but no how-to manual that I know of;
>>>>>> some
>>>>>> topics
>>>>>> that come to mind:
>>>>>>
>>>>>> (1) nouns and verbs,
>>>>>> (2) autoloading simplifying functions,
>>>>>> (3) simplification--how much is too much,
>>>>>> (4) reflection rules,
>>>>>> (5) binary64 & bigfloat evaluation,
>>>>>> (6) extras: gradef, conjugates, limits, TeX properties,
>>>>>> antiderivatives,
>>>>>> (7) declaring function properties (complex, ...),
>>>>>> (8) domain and wrong number of argument errors,
>>>>>>
>>>>>> --Barton
>>>>>>
>>>>>>
>>>>>>
>>>>> _______________________________________________
>>>>> Maxima mailing list
>>>>> Maxima at math.utexas.edu
>>>>> http://www.math.utexas.edu/mailman/listinfo/maxima
>>>>>
>>>>>
>>>>
>>>>
>>>
>