Questions tagged [wavelet-analysis]
Questions on the wavelet analysis functions of Mathematica.
70 questions
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How to know the formula of function in mathematica?
When I review BiorthogonalSplineWavelet in official website.
I could not find any formula of how to calculate as below:
How to ...
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How to plot time-frequency evolution based on zero crossings?
In a paper that analyzes the data from GW150914, a time-frequency plot was shown.
The paper proposes that, quote:
An approximate version
of the time-frequency evolution can also be obtained
directly ...
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Continuous wavelet transform with complex shannon wavelet [duplicate]
The complex Shannon function is defined as:
It seems that Mathematica doesn't support the complex Shannon transform although it supports the real Shannon function. I need the complex Shannon function ...
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Fourier factor and Fourier transform for wavelet transform [duplicate]
To define the continuous wavelet transform in Mathematica, you need Fourier factor and Fourier transform. I don't understand how to find these two, for example, how can define these two in the haar ...
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Plot wavefronts of Laguerre-Gaussian modes
I am trying to plot wavefronts of Laguerre-Gaussian modes, and want to show the changing number of twists with the change in l values. If anyone has the code or any insights. Kindly help me about it. ...
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Orthonormal Wavelet functions
The wavelet function "WaveletPsi" is supposed to create an orthonormal basis of some space.
Now consider e.g. the following wavelet function:
...
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Discrete wavelet transform with complex shannon wavelet
The complex Shannon function is defined as:
It seems that Mathematica doesn't support the complex Shannon transform although it supports the real Shannon function. I need the complex Shannon function ...
0
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1
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161
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Calculate wavelet coefficients with Mathematica
Let $\operatorname{rect}(x)$ be a constant function equal to 1 with support $[-1 / 2,1 / 2]$. Define a step function using the sequence as
$$ f(x)=\sum_{k=1}^4 a_k \operatorname{rect}(x-k)$$
where $...
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Identifying an envelope function of a wave-packet [duplicate]
I have this wavepacket, which is defined over an interval $[a,b], \ a,b\in \mathbb{R}$. Suppose the wavepacket is complex trigonometric and analytic, then how can I find, using any formula or ...
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Image Segmentation for Grid and fence of cage in Frequency Domain
I want to analysis the pattern of this kind of grid of cage, and remove them in frequency domain.
The goal image is like that shown by imgFinal, it's not an ...
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One dimensional wave equation -numerical vs analitcal solution? [closed]
Recently I have been experimenting with one dimensional wave equation with Dirichlet boundary conditions. So the problem goes like this:
I found this formulas in: Qiong-Gui Lin "Yet another ...
- 21
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Defining a new wavelet (Fibonacci wavelet)
I want to define a new wavelet (Fibonacci wavelet) in the reference.
So, I read the tutorial on Wolfram Site, @Jason B. ' s answer, and also @Sektor 's answers.
But I still have some problems in my ...
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Please explain this syntax: GaborWavelet[6]["FourierFactor"]
I've been using Mathematica for some years, yet I'm befuddled by this statement:
GaborWavelet[6]["FourierFactor"]
It appears to give the center frequency ...
- 467
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Is there a way to add a cone of influence to waveletscalogram?
This question was asked in 2013, but didn't get an answer. Can Mathematica plot the cone of influence in wavelet analysis. Matlab will do it.
Follow up question. Does it make good mathematical ...
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Cannot take DWT of parsed data
I have some data in foo.tsv, and I would like to take the DiscreteWaveletTransform of one column. My data looks like this:
...
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