Linked Questions

9
votes
2answers
2k views

plotting a trig functions along with its envelope

Note: This questions is quite different from the ones referred to in the comments. Those deal with numerical questions, while this one is algebraic. I have plots of the following type: ...
7
votes
2answers
6k views

How to get the frequency information of an mp3 audio?

I have: music = Import["http://www.qlcoder.com/uploads/145425353234642.mp3", "mp3"] Then I get: But what I want to get is ...
19
votes
1answer
5k views

How to demodulate an FM signal in continuous-time?

I'm not sure if this is a math or Mathematica question, but I'm posting it here because I'm interested in possible Mathematica tools/functions to solve the problem. I'm stuck. I want to simulate ...
7
votes
3answers
870 views

Envelope for harmonic oscillator [duplicate]

I am able to take the expression $\cos 11t-\cos 12t$ and use the sum to product identity to write it in the form $$\left(2\sin\frac t2\right)\sin\frac{23}{2}t.$$ I can then plot the function and use ...
5
votes
1answer
322 views

Solving partial differential equation involving Hilbert transform

While solving one research paper published in Physical Review Letters, I came across the following equation and I am unable to solve it. $$\frac{\partial f}{\partial t}−(\mathcal{H}(f)\left(\frac{\...
4
votes
1answer
327 views

How to speed up the integral in NDSolve?

On the MMA.SE, there have been several question on how to solve equations including integral using NDSolve, see example 1, example 2, and example 3. Many people, ...
3
votes
1answer
136 views

PrincipalValue option of Convolve not working in 9.0.1?

The PrincipalValue option of Convolve is used in this question to define the Hilbert transform. However, in Mathematica 9.0.1, ...
1
vote
1answer
207 views

Convolution integrals

I want to calculate the following integral $$\int_{-\infty}^{\infty} d \omega f(\omega) g(\omega'\pm\omega)$$ where $f$ has the form $$f(\omega)=\frac{a}{\omega- \omega_0\pm i \eta}$$ and $g$ has a ...
2
votes
1answer
134 views

Plot nested integration of an InterpolatingFunction efficiently

Suppose we have an InterpolatingFunction from NDSolve ...
6
votes
0answers
191 views

Implementation of the Riesz transform

Implementing the Hilbert transformation \begin{equation}H(f)(x) = \frac{1}{\pi}\lim_{\varepsilon \to 0} \int_{|x-y|>\varepsilon} \frac{1}{x-y}f(y) \, dy,\end{equation} appropriate for 1-...
1
vote
0answers
219 views

Implementing Kramers Kronig Relation in Mathematica for Reflection Spectrum

I'm new to Mathematica and I have to solve this problem but all of my approaches are wrong :( So, please can anyone help me with this equation? Here it is: Here is my data : https://pastebin.com/...