MathGroup Archive 2002

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: FullSimplify[Abs[Sign[x]],x>=0] equals 1?


Alain Cochard <al2 at noos.fr> wrote:
> Is the following behavior normal?
>
> In[1]:= Simplify[Abs[Sign[x]],x>=0]
>
> Out[1]= Abs[Sign[x]]
>
> In[2]:= FullSimplify[Abs[Sign[x]],x>=0]
>
> Out[2]= 1

Is this behavior similar to simplifying x/x to 1, even when x might be 0?
Maybe not. Anyway, you might be amused at the result of a typographical
error. (I had _intended_ to type logical OR, instead of logical AND.)

In[1]:= Simplify[Abs[Sign[x]], x>0 && x==0]

Out[1]= 1

Curious!

  David

-- 
-------------------- http://NewsReader.Com/ --------------------
                    Usenet Newsgroup Service


  • Prev by Date: "math1" and "math4" font conversion problem
  • Next by Date: Re: FullSimplify[Abs[Sign[x]],x>=0] equals 1?
  • Previous by thread: FullSimplify[Abs[Sign[x]],x>=0] equals 1?
  • Next by thread: Re: FullSimplify[Abs[Sign[x]],x>=0] equals 1?