Graphing fequence of the signal

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The discussion focuses on the Fourier transform of a discrete signal defined as x(n) = n for 0 <= n < 4 and 0 otherwise, leading to the expression for X(W) as a sum of complex exponentials. Participants emphasize that F(W) has not been defined, making it unclear how to graph it, while X(W) appears to be the Fourier series expansion. For a continuous signal x(t) = t over the same interval, the integral for X(W) is provided, but again, F(W) remains undefined. The conversation highlights the need for clarity on the definitions and relationships between the signals and their transforms. Overall, the participants suggest plotting the real and imaginary parts of the complex exponentials or their trajectories in the complex plane for visualization.
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Say x(n) = n for 0 <= n < 4 and 0 o.w.

So X(W) = Sum n=-∞ to ∞ x(n) exp(-inw) = sum from n=0 to 3 nexp(-inw)
= 0 + exp(-iw) + 2exp(-j2w) + 3 exp(-j3w)

How would I graph F(W)?


Also if the signal was continuous x(t) = t for the same interval

X(W)= integral 0 to 4 texp(-iwt) dy = (4exp(-i4w)/ -iw) - (exp(-iw4) -1)/w^2

How would I graph F(W) for this?
 
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cutesteph said:
Say x(n) = n for 0 <= n < 4 and 0 o.w.

So X(W) = Sum n=-∞ to ∞ x(n) exp(-inw) = sum from n=0 to 3 nexp(-inw)
= 0 + exp(-iw) + 2exp(-j2w) + 3 exp(-j3w)

How would I graph F(W)?
You wouldn't - no F(W) has been given.
You have an X(W) - which seems to be the fourier-series expansion of x(w) or something.
As it is written, it does not seem to depend on W though - but on w.
It helps if you say what things are.

Anyway - if your problem is to graph a sum of complex exponentials - you'd either plot the real and imaginary parts separately or plot the trajectory in the complex plane.

Also if the signal was continuous x(t) = t for the same interval

X(W)= integral 0 to 4 texp(-iwt) dy = (4exp(-i4w)/ -iw) - (exp(-iw4) -1)/w^2

How would I graph F(W) for this?
Again - no F(W) or any indication how it may be related to x or X. Same advise I guess.
 
I mean X(F).
 
I don't see any X(F) either.
What are these things supposed to represent?
 
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