Questions tagged [fourier-analysis]
Questions on the discrete and continuous Fourier analysis functions of Mathematica, as well as the FourierSeries` package.
729 questions
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Reproducing a known Fourier transform
I am trying to reproduce a well known Fourier transform result from a paper, and the paper cites the result from a table of integrals in a big book that lists known results.
This is how the paper ...
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Simplification of terms C Exp[a+b x] to C Exp[a]Exp[bx]
I have an expression of the form
C1 Exp[a1+b1 x] + C2 Exp[a2+b2 x] + C3 Exp[a3+b3 x] + ...
Where variables C, ...
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What are possible ways to avoid DiracDelta[ω] in Fourier transforms? [closed]
I found one related question here, but I am looking for other possible solutions for this DiracDelta function in the Fourier transform.
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Plotting Fourier Transforms: Wave Equation (1D)
I tried to solve the following wave equation on Mathematica, and the code worked well so far, but when I tried to plot the results, Mathematica froze and I do not know why.
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Numerical inverse Fourier Transform of a singular function
I'm working on computing the inverse Fourier transform of a function derived from a matrix construction involving a Poisson-weighted system. Here's the relevant setup.The main object is a matrix-...
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How can I compute the spatial autocorrelation function from a PDE simulation?
I have a system of PDEs defined over a square domain. The dependent variables are $a(t,x,y),b(t,x,y),c(t,x,y)$, and the system uses Dirichlet boundary conditions with initial conditions defined as ...
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How can I get the power spectrum and mean power of my signal?
I have measured this signal over time (where x is time in seconds and y is AC in D):
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Trouble in taking the Fourier transform and drawing a plot
I have experimented in the lab and recorded data in an Excel file. The first column of the file is "time", and the rest are "amplitude". I want to take the Fourier transform of ...
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Frequency identification via Fourier when wave period is larger than dataset length
The following code is taken from the manual
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Difficult inverse Fourier transform computation
I need the expression of the function $G(x)$ for which I have only the Fourier transform:
\begin{equation}
G(x)= \int_{-\infty}^{\infty} \frac{ dp}{2 \pi}e^{i p x} \frac { \sinh\left( \frac{ \pi p(1-\...
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Difficult Fourier transform
I need to compute the Fourier transform of a simple rational function times hyperbolic secant distribution
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Can I make double discrete Fourier transform produce the reverse of data?
Fourier[Fourier[{1,2,3,4}]] gives {1,4,3,2} instead of a mirror image {4,3,2,1}. Is there a ...
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Help with Fourier[] [duplicate]
When I create a list of discrete measurements of a sine wave and then use Fourier[] to transform it, I get a peak on the frequency axis that is characteristically less than the measured frequency and ...
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When trying to graph a 2D Fourier transform - cannot evaluate numerically
I am trying to graph the 2D Fourier transform of the function:
(x + I y) BesselJ[1, Sqrt[x^2 + y^2]].
However, I noticed that upon trying to evaluate this function, ...
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