MathGroup Archive 2007

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

Search the Archive

Re: Bug with Limit?

  • To: mathgroup at
  • Subject: [mg73952] Re: Bug with Limit?
  • From: Bill Rowe <readnewsciv at>
  • Date: Sat, 3 Mar 2007 01:19:24 -0500 (EST)

On 3/2/07 at 6:34 AM, sterraza at (Sergio Miguel Terrazas
Porras) wrote:

>I was teaching a class and was discussing discontinuous functions.
>We came across f(x) = Abs(x)/x, and g(x) = 1/(x-3). The first does
>not have a limit as x -> 0 and the second does not have a limit as x
>-> 3. The unilateral limits of both are different. When I specified
>the direction, Mathematica 5.1 gave the correct answer. However,
>when no direction was specified, Mathematica 5.1 gave (seemingly) by
>default the value of de right handside limit.

>This is plain wrong, and could lead to problems, specially for a
>student. Any comments?

While it might confuse a student this behavior is not a bug. As
is the case for many other functions, when an option is not
specified Mathematica defaults to something that may or may not
be suitable for what you are trying to do. It is up to the user
to be aware of such issues and specify the correct options.
To reply via email subtract one hundred and four

  • Prev by Date: Re: Integrals involving square roots
  • Next by Date: Cases to Select ?
  • Previous by thread: Re: Bug with Limit?
  • Next by thread: Re: Bug with Limit?