Re: Mathematica cannot simplify a product of UnitStep functions

*To*: mathgroup at smc.vnet.net*Subject*: [mg55153] Re: Mathematica cannot simplify a product of UnitStep functions*From*: dh <dh at metrohm.ch>*Date*: Mon, 14 Mar 2005 03:44:02 -0500 (EST)*References*: <d1141c$cnc$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Hello Alain, this seems to have been fixed. In Mathematica 5.1 Windows it simplifies to zero. Sincerely, Daniel Alain Cochard wrote: > Consider the following: > > Mathematica 4.0 for Linux > Copyright 1988-1999 Wolfram Research, Inc. > -- Motif graphics initialized -- > > In[1]:= e1=UnitStep[x-y]; e2=UnitStep[x-z]; > > In[2]:= FullSimplify[{e1,e2,e1*e2},x<y<z] > > Out[2]= {0, 0, UnitStep[x - y, x - z]} > > I find it strange that it cannot simplify the product to 0. Is there > something mathematically profound here, implying that the true result > is indeed not 0?? (At least I hope it's not something trivial!) > Assuming the answer is no, is there a smarter/more elegant way to > perform the simplification than the workaround I found, which is to > simplify each term and multiply them. > > Thanks in advance. > AC > >