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I'm the person that was asking about FT a few weeks ago. I completely understand DFT now, but my paper is on FT, and I thought I can derive FT from DFT.

 

I am aware DFT can be expressed as:

\(X_k=\sum_{n=0}^{N-1}{x_n}\cos{\Big(\frac{2{\pi}kn}{N}\Big)} - i\sum_{n=0}^{N-1}{x_n}\sin{\Big(\frac{2{\pi}kn}{N}\Big)}\)

Using Euler's theorem.  Comparing the actual definitions of FT and DFT, I would think that FT is just DFT with an "infinite" sampling rate. This would change the summation to an integral (I'm right about this?), but the frequency k/N would approach 0? Why would this work out? 

 
 Jan 19, 2016

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