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Re: Fourier and InverseFourier


Bill Rowe wrote:
> On 5/2/07 at 3:56 AM, josh2499 at hotmail.com (rob) wrote:
> 
> 
>>Hi, thanks for responding. No, I'm not sure it exists. I tried
>>Exp[-t^2] and it doesn't work either. I haven't yet found a case
>>where InverseFourierTransform[] works so I suspect I'm still doing
>>something wrong.
> 
> 
> Are you certain you've not previously defined one or more of the
> variables before attempting the InverseTransform? I have no
> difficulty with eitehr Exp[-t] or Exp[-t^2] here. That is:
> 
> In[1]:=
> InverseFourierTransform[Exp[-t], t, w]
> 
> Out[1]=
> Sqrt[2*Pi]*DiracDelta[w - I]
> 
> In[2]:=
> InverseFourierTransform[Exp[-t^2], t, w]
> 
> Out[2]=
> 1/(E^(w^2/4)*Sqrt[2])
> 
> In[3]:=
> $Version
> 
> Out[3]=
> 5.2 for Mac OS X (June 20, 2005)
> --
> To reply via email subtract one hundred and four
> 
Here's what doesn't work for me:
fs = FourierTransform[UnitStep[t]*Sin[t], t, w]
fe = FourierTransform[UnitStep[t]*Exp[-t], t, w]
x3[t_] := InverseFourierTransform[fs*fe, w, t]
Plot[x3[t], {t, 0, 15}, PlotRange -> All]

What do you get? Thanks.


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