FFT in mathematica

*To*: mathgroup at smc.vnet.net*Subject*: [mg113650] FFT in mathematica*From*: Gazi Habiba Akter <gazihabiba02 at gmail.com>*Date*: Sat, 6 Nov 2010 04:59:21 -0500 (EST)

Hi, I don't understand how fft algorithm works. but i have to solve a problem by Mathematica code .I am not math and physics student it need my thesis work. it will be ok if any body explain by a simple function. .I tried to solve this problem using fourier transform in mathematica directly but it does not work.I think i need to modify my function or need to know how FFT works for my problem. Here is my code ClearAll["Global'*"] z = 0; n = 100; v1 = 0.5*(1 + Tanh[n*t]); x = (2*t (1 + z))^0.5; v2 = Hypergeometric1F1[.5, 1, -2 x]; v3 = Exp[x - t]; r1 = v1*v2*v3; f = FourierTransform[r1, t, v]; w1 = InverseFourierTransform[f*Exp[z/2*(1 - I*v)], v, t] I need the plot of w1 with respect to t for different value of Z. here r1 is only for z=0. it will be great for me if anybody help me. Thanks, rupa