DTFT vs. DFT: Example #6: sum of cosine waves (DC, (1+1/6) Hz, (2+1/6)Hz)

Sampled sequence 

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Magnitude plot of DTFT as a function of frequency 

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Phase plot of DTFT as a function of index k 

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Magnitude plot of DFT as a function of frequency 

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Phase plot of DFT as a function of index k 

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Rearrange and scale DFT result 

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Show all 

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Converted by Mathematica      March 25, 2003