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Jan
29
comment Fourier spectrum reflected across origin and Nyquist frequency
My point being that you can't just magically 'get rid of' the negative frequencies.
Jan
29
comment Fourier spectrum reflected across origin and Nyquist frequency
Loosely, there is a collection of functions that are used to characterize the behaviour of $t \mapsto f(t)$. The usual choice in this context are the functions $t \mapsto e^{i \omega t}$, less usually are the functions $t \mapsto \cos (\omega t), t \mapsto \sin (\omega t)$. Using one function with 'negative' frequency (I think of it as an index rather than a negative) is more convenient that pairs of functions with non-negative frequencies. The bandwidth is a measure of the number of such functions needed to represent the signal. That, at some level, doesn't change with representation.
Jan
29
comment Is there a systematic way of resolving sequences of dots in figures?
I don't know how to help unless you are more specific about the characterization of the figures.
Jan
29
comment Is there a systematic way of resolving sequences of dots in figures?
Just be counting it must be $2n+1$.
Jan
29
comment Is there a systematic way of resolving sequences of dots in figures?
What do you mean by 'get the formula' and 'resolve it'?
Jan
29
revised How to use matlab for plotting functions that contain summations?
added 55 characters in body
Jan
29
comment How to use matlab for plotting functions that contain summations?
fplot(@f,[0,10]) seems to work fine in Octave...
Jan
29
comment Does analytical solution exist for this convex euclidean affine projection problem with non-negativity constraints?
Unless $A$ has some restrictions, I doubt that an analytic solution exists, but the above can be formulated as a quadratic program. In fact, it is a nearest point computation to a compact, convex set. On simple (slow) approach would be the Frank–Wolfe algorithm.
Jan
29
revised how to prove matrix addition is continuous under certain matric topology?
grammar, mathjax
Jan
29
comment how to prove matrix addition is continuous under certain matric topology?
See en.wikipedia.org/wiki/Vectorization_%28mathematics%29 for the latter.
Jan
29
answered how to prove matrix addition is continuous under certain matric topology?
Jan
29
comment How to use matlab for plotting functions that contain summations?
@ConradTurner: Thanks! I can't bring myself to pay for a Matlab license. I used to use Moler's free Fortran version...
Jan
29
answered How to use matlab for plotting functions that contain summations?
Jan
29
comment How to use matlab for plotting functions that contain summations?
Why don't you just add all terms instead of summing them by some other method?
Jan
29
comment How to use matlab for plotting functions that contain summations?
Why? It is straightforward to write an expression with all 6 terms?
Jan
29
comment Points on a straight line (Complex Analysis)
Yes, $z_0$ is a point on the line and $d_0$ is the direction. I don't understand your next sentence. It is much the same as a line in $\mathbb{R}^2$ with the exception that we can divide points in $\mathbb{C}$.
Jan
29
revised Existence of solution for linear matrix inequality?
grammar
Jan
29
comment Existence of solution for linear matrix inequality?
Look for a solution to the appropriate linear program.
Jan
29
comment How do I solve Euler Lagrange equation for image de-blurring?
I don't know how to solve your problem, but for the sake of one equation, you should use MathJax and add it to the question.
Jan
29
answered Points on a straight line (Complex Analysis)