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Timeline for Convolution in frequency domain

Current License: CC BY-SA 3.0

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Nov 20, 2015 at 14:24 comment added Matt L. @DilipSarwate: Note that it's an odd length DFT, that's why there is no bin at Nyquist. The two 0's are the (conjugate complex) elements at indices $-2$ and $2$, just below Nyquist.
Nov 20, 2015 at 14:20 comment added Dilip Sarwate Why does A equal ` [0,-j,0,0,j]` ? I am puzzled by the two 0's in a row.
Nov 20, 2015 at 13:17 history edited Matt L. CC BY-SA 3.0
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Nov 9, 2015 at 19:36 comment added Dole L Thanks, I forgot that positive imaginary part actually reflects inverted sine wave, that threw me off a bit there. Indeed I had the spectrum from negative to positive and you have it from 0 up.
Nov 9, 2015 at 18:35 comment added Matt L. @Dole: They are symmetric: the first element is the zeroth bin (DC), the second element is bin number 1 (the frequency of the sinusoid); and the last element is bin number -1 (the negative frequency of the sinusoid). Try to see it by periodic continuation of the vector: (...,0,j,[0,-j,0,0,j],0,-j,...)
Nov 9, 2015 at 17:25 comment added Dole Where does that frequency domain representation of the sine wave come from? Don't the negative and positive parts always need to be symmetric around the DC offset bin?
Nov 9, 2015 at 16:43 vote accept Dole
Nov 9, 2015 at 16:43 vote accept Dole
Nov 9, 2015 at 16:43
Nov 8, 2015 at 20:23 history edited Matt L. CC BY-SA 3.0
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Nov 8, 2015 at 19:05 history edited Matt L. CC BY-SA 3.0
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Nov 8, 2015 at 19:00 history answered Matt L. CC BY-SA 3.0