Re: FoourierTransform of a function defined in sections
- To: mathgroup at smc.vnet.net
- Subject: [mg70190] Re: FoourierTransform of a function defined in sections
- From: Roland Franzius <roland.franzius at uos.de>
- Date: Sat, 7 Oct 2006 07:07:02 -0400 (EDT)
- Organization: Universitaet Hannover
- References: <eg4soa$ffu$1@smc.vnet.net>
Eckhard Schlemm schrieb: > Hello, > > I want Mathematica to calculate the FourierTransform of a function which is > defined by Sin[x]^2 for Abs[x]<PI and zero else. I tried and defined the > function g as follows: > > g[x_]:=If[Abs[x]>PI,0,Sin[x]^2]; > Should be Pi instead of PI I assume > That works fine. But if I have mathematica try to determine the > FourierTransform by > > FourierTransform[g[x],x,p] > > I always get the error that the recursion limit and the iteration limit were > exceeded... > > what am I'm doing wrong? No idea. Recursion error may indicate that g or x or p have values already? g[x_] := UnitStep[Pi - x]UnitStep[Pi + x] Sin[x]^2 FourierTransform[g[x], x, k] -((2*Sqrt[2/Pi]*Sin[k*Pi])/(-4*k + k^3)) h[x_] := If[-Pi < x < Pi, Sin[x]^2, 0] FourierTransform[h[x], x, k] -((2*Sqrt[2/Pi]*Sin[k*Pi])/(-4*k + k^3)) -- Roland Franzius