MathGroup Archive 2003

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

Search the Archive

Re: Maybe it's me but the integrator at wolfram doesn't work very well

  • To: mathgroup at smc.vnet.net
  • Subject: [mg44978] Re: Maybe it's me but the integrator at wolfram doesn't work very well
  • From: bobhanlon at aol.com (Bob Hanlon)
  • Date: Fri, 12 Dec 2003 04:41:14 -0500 (EST)
  • References: <br9i4v$d22$1@smc.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

The Integrator works fine on this problem.

ln x is not Log[x] it is x times a variable named ln that is assumed to be
independent of x

Enter the expression as 1/x Log[x]

Bob Hanlon

In article <br9i4v$d22$1 at smc.vnet.net>, geoman <geogeo9090 at yahoo.com> wrote:

<< Firstly the "integrator" tool at wolfram evaluates the indefinite integral.
Fine
 
 
Here are some examples of incorrect answers of the "integrator"
 
INT means the integral sign
 
INT 1 / x ln x
 
Don't feel bad though I found another site at mss.vanderbilt.edu that got it
wrong as well
 
Now this is quite a fundamental integral but is it hopelessly botched by the
"integrator."
 
 
Here is another
 
INT ln x
 
the "integrator" got that wrong as well.  I did find a site that got it right
though.
 
Where the error lies I don't know but do in fact think it may be somewhere in
the original mathematica code.
 
BTW can anyone on this list give me the correct answers to the above
thanks  geo.


  • Prev by Date: Re: log-log plot with error bars, different data markers
  • Next by Date: Evaluation of AiryAi
  • Previous by thread: Maybe it's me but the integrator at wolfram doesn't work very well
  • Next by thread: Re: Maybe it's me but the integrator at wolfram doesn't work very well