Re: NIntegrate
- To: mathgroup at smc.vnet.net
- Subject: [mg44820] Re: [mg44794] NIntegrate
- From: Anton Antonov <antonov at wolfram.com>
- Date: Wed, 3 Dec 2003 04:24:02 -0500 (EST)
- References: <200311271638.LAA19984@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Zheng Yang wrote:
>Hi,
>
>I'd like to ask why the first expression below takes so much longer to finish than the second. They look same to me.
>
>\!\(N[â?«\_1\%â??\((x - 1)\)^ .5\ \(1\/\(1 + Exp[\((x -
> 2)\)/2]\)\) \[DifferentialD]x]\)
>
>\!\(NIntegrate[\((x - 1)\)^ .5\ 1\/\(1 + Exp[\((x - 2)\)/2]\), {x, 1, â??}]\)
>
>And I'd like to know if this apply to other numerical functions.
>
>Thanks a lot,
>
>Zheng
>
>
Hi,
Would you please send the input form of your Mathematica expressions!
The meaning of the symbols
â?«\_1\%â??\
is not clear.
It seems to me that your code is incomplete. For example, the second
line of your code gives to NIntegrate a symbolic range for the variable
x, so NIntegrate doesn't make any calculations.
Anton Antonov
Wolfram Research, Inc.