Integration bug
- To: mathgroup at smc.vnet.net
- Subject: [mg38474] Integration bug
- From: "Dana DeLouis" <delouis at bellsouth.net>
- Date: Wed, 18 Dec 2002 01:54:25 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
I am new to Mathematica also, but I seem to recall a bug in the use of
the variable ?d" before also. This was the first thing I thought of.
Changing ?d" to something like ?z? gives the answer of Pi.
Removeall
All Global` variables Removed!
$Version
4.2 for Microsoft Windows (June 5, 2002)
Integrate[Sin[z + x]/(z + x), {x, -Infinity, Infinity}]
Pi
Integrate[Sin[d + x]/(d + x), {x, -Infinity, Infinity}]
0
(Note: Removeall is my own function that removes all global variables
and is included to show that all variables are cleared.)
Dana DeLouis
Windows XP
$VersionNumber -> 4.2
= = = = = = = = = = = = = = = = =
"David W. Cantrell" <DWCantrell at sigmaxi.org> wrote in message
news:at4cv9$eta$1 at smc.vnet.net...
> Using version 4.1,
>
> Integral[Sin[x+d]/(x+d),{x,-Infinity,Infinity}] yields 0 .
>
> This is, of course, incorrect. (Does version 4.2 make this error
also?)
>
> Mathematica does Integral[Sin[x]/x,{x,-Infinity,Infinity}] correctly
> however, yielding Pi, which should also be the answer for the original
> integral (regardless of the value of d).
>
> Does anyone have an idea why Mathematica gets the original integral
wrong?
>
> David Cantrell
>
> --
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