Linked Questions
44 questions linked to/from What do the X and Y axis stand for in the Fourier transform domain?
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1answer
72 views
How can I make an FFT in Mathematica using data from a file? [closed]
I need to calculate the seismic moment of an earthquake data, but I don't know how the FFT is applied in some data, my data is a plain text that I must import it to Mathematica
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2
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0answers
100 views
Why does Mathematica Fourier transform of finite sequence of numbers require parameters? [closed]
I apologize if this is a basic question, but here goes: The Discrete Fourier transform of a sequence of N complex numbers is uniquely defined by eq.1 in this wiki page,
https://en.wikipedia.org/wiki/...
1
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1answer
79 views
Fast method for numerical integral (Fouriertransform?)
I want to numerically compute following integral (as fast as possible):
\begin{equation}
f(x) = \left| \int e^{ \mathrm{i} p x / 2} f(p) \ \mathrm{d}p\right|^2 ,
\end{equation}
where $f(p)$ is given ...
0
votes
1answer
118 views
Using Fourier to get the numerical FT of a Gaussian [duplicate]
I've been trying to find the FT of a more complicated function, but it seems my method is wrong. To check, I tried to calculate the FT of a Gaussian numerically. This is what I did:
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1
vote
0answers
38 views
Taking Fourier transform with WolframAlpha gives unexpected result [duplicate]
I have noticed that WolframAlpha's definition of the Fourier Transform is different than the one in my book of formulas. In my book the Fourier transform of $f(t)$ is defined as:
$$\int_{-\infty}^{\...
1
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1answer
107 views
Finding frequency of oscillation of an particle by Fourier analysis of the trajectory [duplicate]
I am trying to find the resonant frequency of a particle by Fourier analysis of the trajectory.
Here is the data file.
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0
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0answers
52 views
Finding Fourier transform of a quantity v/s theta (0 to 360 degrees)
I have a physical quantity (experimentally measured) lets say T whose variation I have measured with angle (theta in degrees). I want to find out the Fourier components of this quantity with respect ...
3
votes
1answer
56 views
How does the Fourier transform take its input?
I'm using the Fourier command and I'm wondering how does it take its imput. I know that it takes a list of numbers representing a function of time and it gives back a list of numbers representing a ...
1
vote
0answers
113 views
Taking numerical Laplace transform of a tabulated data with Mathematica?
I am relatively new to the use of Mathematica in the context of numerical evaluations, therefore I would greatly appreciate a detailed answer and would like to express my gratitude towards any help in ...
0
votes
1answer
286 views
Discrete fourier transform and convolution — scaling factor?
I am trying to convolve a square wave (a diffraction grating phgrating with slits size \[CapitalLambda]) with a point spread ...
2
votes
2answers
198 views
Figuring out the frequency components using FFT [duplicate]
The function defined below has three frequencies 2, 4 and 10. How to use the Fourier transform (FFT) to show these frequencies?
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0
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1answer
123 views
Identifying the three frequencies using fourier transform
The following simple function has clearly three frequency components:
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0
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1answer
103 views
How to fit one function into the form of another?
I have a slightly complicated periodic function of one variable t, say g[t].
I want to do a least squares fit of that function ...
0
votes
1answer
194 views
Finding frequency from Fourier transform [closed]
I tried to find frequency using Fourier Transform, but notice that my code have some mistakes which I can't find.
So, my code is below:
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0
votes
1answer
228 views