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I need to compute an inverse Fourier transform, I did this previously by writing my own inverse Fourier transform routine which worked pretty well on simple examples but I am currently investigating some rather obscure wave profiles. 
Subject: Inverse Fourier transforms From: Walter Roberson Date: 17 Jun, 2010 19:45:30 Message: 2 of 32 
Mat Hunt wrote: 
I want to compute an inverse Fourier transform and plot the solution. I have the analytical expression of the inverse Fourier transform. I can either supply it as an analytical function (and use ifourier) or give it as a numerical array and use ifft. 
Subject: Inverse Fourier transforms From: Walter Roberson Date: 17 Jun, 2010 21:58:52 Message: 4 of 32 
Mat Hunt wrote: 
Walter Roberson <roberson@hushmail.com> wrote in message <hve5un$mj1$1@canopus.cc.umanitoba.ca>... 
Subject: Inverse Fourier transforms From: Walter Roberson Date: 18 Jun, 2010 02:59:39 Message: 6 of 32 
Mat Hunt wrote: 
No, there are no problems with it, no complex numbers. The integrand is an even function and real, as a result, the complex part of the solution is zero. 
So, the best way to perform this calculation is numerically. In which case how would I go about this using matlab's inbuilt functions. I wrote a small program myself: 
Subject: Inverse Fourier transforms From: Walter Roberson Date: 18 Jun, 2010 13:37:34 Message: 9 of 32 
Mat Hunt wrote: 

Subject: Inverse Fourier transforms From: Walter Roberson Date: 19 Jun, 2010 15:53:45 Message: 11 of 32 
Mat Hunt wrote: 
On Jun 17, 6:29 pm, "Mat Hunt" <hunt_...@hotmail.com> wrote: 
On Jun 18, 6:04 am, "Mat Hunt" <hunt_...@hotmail.com> wrote: 
On Jun 18, 9:37 am, Walter Roberson <rober...@hushmail.com> wrote: 
Hi Greg, 
On Jun 20, 6:33 am, "Mat Hunt" <hunt_...@hotmail.com> wrote: 
Greg Heath <heath@alumni.brown.edu> wrote in message <4cbcef891c164d588eab7da8e0e7eff2@r27g2000yqb.googlegroups.com>... 
On Jun 20, 3:16 pm, Greg Heath <he...@alumni.brown.edu> wrote: 
Hi Greg, 
On Jun 21, 5:42 pm, "Mat Hunt" <hunt_...@hotmail.com> wrote: 
Hi Greg, 
On Jun 23, 6:58 am, "Mat Hunt" <hunt_...@hotmail.com> wrote: 
On Jun 23, 1:38 pm, Greg Heath <he...@alumni.brown.edu> wrote: 
Hi Greg, 
So can anyone give me a clear and simple methodology to go from a Fourier transformed function F(k), back to the original function at a point, x say? So this would be a single number? I would have thought the the people at matlab would have thought this one through. 
On Jun 24, 3:13 pm, "Mat Hunt" <hunt_...@hotmail.com> wrote: 
Okay, all I am asking is if I give a function F=F(k) which is the Fourier transform of a function f=f(x) and another point x, say then I have a number as an output which is f(x). Can the ifft function do this? 
On Jun 27, 3:57 pm, "Mat Hunt" <hunt_...@hotmail.com> wrote: 
The problem is that my function isn't periodic. I am looking for a travelling wave solution which vanishes as x\rightarrow\pm\infty 
On Jun 28, 6:15 am, "Mat Hunt" <hunt_...@hotmail.com> wrote: 
Sorry for bringing up an old post, but this was a high rated link when googleing the problem and I didn't find a satisfactory solution. So I want to share the solution. Say I start with 
"M Antola" <matti.antola@helsinki.fi> wrote in message <kfgclo$4ot$1@newscl01ah.mathworks.com>... 
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