I need to use the discrete Fourier transform for function that represented as list of values. I started with an easy task to check my understanding. I tried to get the amplitude values for `2*Sin[x]`. I think they should be somwhere about 2. But using the discrete `Fourier` operation produces something quite different. Can someone tell me where my mistakes are? Here is what I tried. data = Table[2*Sin[x], {x, 0, 100}]; ListPlot[data, Joined -> True] ![enter image description here][1] ListPlot[Abs[Fourier[data]], Joined -> True, PlotRange -> All] ![enter image description here][2] ListPlot[ Table[Abs[FourierTransform[2*Sin[x], x, w]] /. DiracDelta -> DiscreteDelta, {w, 0.1, 10, 0.1}], Joined -> True, PlotRange -> All] ![enter image description here][3] [1]: https://i.sstatic.net/YtAVI.jpg [2]: https://i.sstatic.net/ND47Q.jpg [3]: https://i.sstatic.net/0wyzX.jpg How can I get the same results from 'Fourier' as I get from 'FourierTransform'?