Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2003
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 2003

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

Search the Archive

Re: Simplify[Abs[x],x<0]]

  • To: mathgroup at smc.vnet.net
  • Subject: [mg39315] Re: [mg39303] Simplify[Abs[x],x<0]]
  • From: Andrzej Kozlowski <akoz at mimuw.edu.pl>
  • Date: Tue, 11 Feb 2003 04:41:20 -0500 (EST)
  • Sender: owner-wri-mathgroup at wolfram.com

Almost certainly an oversight. However, if you replace Abs by something 
equivalent, things work as they should, e.g:


Simplify[Sqrt[x*Conjugate[x]], x < 0]

-x

or


Simplify[Sqrt[Im[x]^2 + Re[x]^2], x < 0]

-x

etc.




On Monday, February 10, 2003, at 03:07 PM, Uri Zwick wrote:

> Hi,
>
> Simplify[ Abs[x] , x>0 ] returns x.
> But, Simplify[ Abs[x] , x<0] returns Abs[x], and not -x.
>
> Why is that?
>
> Uri
>
>
>
>
Andrzej Kozlowski
Yokohama, Japan
http://www.mimuw.edu.pl/~akoz/
http://platon.c.u-tokyo.ac.jp/andrzej/



  • Prev by Date: To print and not to print
  • Next by Date: Limits: Is there something I'm missing Here?
  • Previous by thread: Re: Simplify[Abs[x],x<0]]
  • Next by thread: Re: Simplify[Abs[x],x<0]]