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Old 2002-10-28, 14:18   #7
wpolly
 
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Sep 2002
Vienna, Austria

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Quote:
Originally Posted by creative1
how did you create the 'i' matrix to be able to make the transform? everything is was very nice explained but i couldnĀ“t get how you filled that matrix with 1, -1, i, -i values
where did that come from?
[code:1]
|+1 +1 +1 +1| |i^0 i^0 i^0 i^0|
|+1 +i -1 -i|=|i^0 i^1 i^2 i^3|
|+1 -1 +1 -1| |i^0 i^2 i^4 i^6|
|+1 -i -1 +i| |i^0 i^3 i^6 i^9|
[/code:1]
For FFT size 2N, just replace the i with cos(pi/N)+i sin(pi/N)(That is, a 2Nth root of 1)and constuct the matrix as above.......


P.S. I am only 14 years old!
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