Re: FourierTransform
- To: mathgroup at smc.vnet.net
- Subject: [mg57667] Re: FourierTransform
- From: "Peltio" <peltio at trilight.zone>
- Date: Fri, 3 Jun 2005 05:34:23 -0400 (EDT)
- References: <d7k36h$oi1$1@smc.vnet.net> <d7mjn3$bvd$1@smc.vnet.net>
- Reply-to: "Peltio" <peltioNOSPAM at despammed.com.invalid>
- Sender: owner-wri-mathgroup at wolfram.com
"dh" wrote >Integrate[Exp[-I*w*t],{t,0,infinity}] >or more accurate: >Integrate[Exp[-I*w*t], {t, 0, Infinity}, Assumptions ->Element[w,Reals]] >should fail to converge because the integrand is a unit vector whose >phase changes with constant velocity (with the exception w=0). However, >Mathematica happily gives the answer: >-I/w It looks as if Mathematica is computing a finite version of the integral Integrate[Exp[-I*w*t],{t,0,b}] getting Exp[-I w b]/(-I w) - Exp[-I w 0]/(-I w) I/w (Exp[-I w b]-1) and then fails to do the limit for b->Infinity, assuming that Exp[- Infinity * something else] is zero Is this a bug of Integrate or Limit? cheers, Peltio invalid address in reply to. ecc. ecc.