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Question 2. | Question 2. | ||
There has to be a decent way to do this by hand. Computing 2 3pt DFTs and then 3 2 pt DFTs is really irritating. | There has to be a decent way to do this by hand. Computing 2 3pt DFTs and then 3 2 pt DFTs is really irritating. | ||
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Suggestions? | Suggestions? | ||
| − | + | :This is an excellent question, which makes me realize that I forgot to say the following in class: "Although the FFT makes the computation of a DFT faster on a computer, it does not make it faster for the DFT that we ask you to compute by hand. The idea is that, for N large, the number of operations needed to compute an FFT is much lower than that for computing a DFT using the formula. However, when we ask you to compute a DFT by hand, N is typically very small, so using the FFT usually only makes things more complicated. For answering Question 2, just use the definition of DFT (the summation formula) to compute it. --[[User:Mboutin|Mboutin]] 21:20, 4 November 2010 (UTC) | |
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| + | [[Hw8ECE438F10|Back to HW8]] | ||
[[2010 Fall ECE 438 Boutin|Back to ECE438, Fall 2010, Prof. Boutin]] | [[2010 Fall ECE 438 Boutin|Back to ECE438, Fall 2010, Prof. Boutin]] | ||
Latest revision as of 17:20, 4 November 2010
HW8 Discussion, ECE438, Fall 2010
Question 2.
There has to be a decent way to do this by hand. Computing 2 3pt DFTs and then 3 2 pt DFTs is really irritating.
Suggestions?
- This is an excellent question, which makes me realize that I forgot to say the following in class: "Although the FFT makes the computation of a DFT faster on a computer, it does not make it faster for the DFT that we ask you to compute by hand. The idea is that, for N large, the number of operations needed to compute an FFT is much lower than that for computing a DFT using the formula. However, when we ask you to compute a DFT by hand, N is typically very small, so using the FFT usually only makes things more complicated. For answering Question 2, just use the definition of DFT (the summation formula) to compute it. --Mboutin 21:20, 4 November 2010 (UTC)
