Re: Another damn simplifying problem: ArcTan
- To: mathgroup at smc.vnet.net
- Subject: [mg59937] Re: Another damn simplifying problem: ArcTan
- From: "Carl K. Woll" <carlw at u.washington.edu>
- Date: Fri, 26 Aug 2005 04:53:26 -0400 (EDT)
- Organization: University of Washington
- References: <dek7hq$a2t$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
"Mathieu McPhie" <m.mcphie at fz-juelich.de> wrote in message news:dek7hq$a2t$1 at smc.vnet.net... > Can someone please explain this to me: (M v4.something) > > In:= Simplify[ArcTan[-x]+ArcTan[x]] > Out= 0 > > In:= Simplify[ArcTan[-x,1]+ArcTan[x,1]] > Out= ArcTan[-x,1]+ArcTan[x,1] > Unfortunately the above isn't zero, even for real x: In[6]:= ArcTan[-.1,1]+ArcTan[.1,1] Out[6]= 3.14159 > Note, I want something more complicated than this obviously. Actually > want something like > > Simplify[ArcTan[-x,y]+ArcTan[x,y]] > > but above is the easiest example of this infuriating programs problem. > > Cheers, Mathieu > Carl Woll Wolfram Research