Re: FullSimplify[Abs[Sign[x]],x>=0] equals 1?
- To: mathgroup at smc.vnet.net
- Subject: [mg33731] Re: FullSimplify[Abs[Sign[x]],x>=0] equals 1?
- From: "David W. Cantrell" <DWCantrell at sigmaxi.org>
- Date: Wed, 10 Apr 2002 00:49:15 -0400 (EDT)
- References: <a8tsnd$fkm$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
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