axiom-math
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Axiom-math] provisos and indeterminates


From: Francois Maltey
Subject: Re: [Axiom-math] provisos and indeterminates
Date: Sun, 22 May 2005 13:19:18 +0200
User-agent: Gnus/5.1006 (Gnus v5.10.6) XEmacs/21.5 (chestnut, linux)

address@hidden about provisio :

>   the proviso idea is fundamental to math but ignored or treated badly
>   by all computer algebra systems. provisos arise in things like:
>
>     1
>    ---   provided x != 0
>     x

Mupad does this :

>> solve (a^2*x-a=x+1, x)
           / {  a + 1 }                                                \
  piecewise| { ------ } if not a in {-1, 1}, C_ if a = -1, {} if a = 1 |
           | {  2     }                                                |
           \ { a  - 1 }                                                /

limit (a*x*exp (a*x), x=+infinity) ; // is unevalued

but this three commands are right :
assume (a>0) ;  limit (a*x*exp (a*x), x=+infinity)
assume (a=0) ;  limit (a*x*exp (a*x), x=+infinity)
assume (a<0) ;  limit (a*x*exp (a*x), x=+infinity)

I don't understand if this packages is in the debian-axiom, 
the 2005-02 version, will be in the next version, or isn't yet in 
one package ?

I'm a first-year university teacher, I used mupad and I think I will use 
axiom because it's really a free program. 

The first question that one colleague ask to me when we speak about computer
algebra is : can I do assume hypothesis with axiom ?

Have a good day !

Fran├žois





reply via email to

[Prev in Thread] Current Thread [Next in Thread]