Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
2000
*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 2000

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

Search the Archive

number types

  • To: mathgroup at smc.vnet.net
  • Subject: [mg21613] number types
  • From: Naum Phleger <naum at cava.physics.ucsb.edu>
  • Date: Tue, 18 Jan 2000 02:35:06 -0500 (EST)
  • Sender: owner-wri-mathgroup at wolfram.com

    I feel sort of silly asking something that should be so clear but after
LOTS of trying I can't seem to get it right.

How can I make Mathematica know that a variable is real or positive so that

Conjugate[a] gives a

Sqrt[ a^2 ] gives a

when I evaluate integrals with a in them it doesn't give me an If statement
like 

If[ Im[a]=0, answer I want   , unevaluated integral ]

    this seems like it should be easy but I nothing that I try ever works.

Thanks for any help.


  • Prev by Date: Re: Plotting A verticle line?
  • Next by Date: a question about complex variable
  • Previous by thread: Re: step fn of sin
  • Next by thread: Re: number types