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Questions tagged [spectral]

145 questions
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Python: Spectral Centroid for a .wav file?

I need do define a "spectral centroid" function that will analyze an audio file but I'm not able to convert the mathematical formula into code. If anybody could help me it would be great, I'm out of ideas. the formula in question…
user3765226
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analyzing time series in the frequency domain

I am attempting to analyse a time series with spectral analysis. I am trying to detect any periodicities in my data, which is composed of hourly measurements recorded for one week (24 * 7 = 168 measurements), I aim to show the diurnal component of…
KatyB
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Social Network data sets that contains a community structure

I am working on a set of spectral clustering methods that can essentially be used to detect a community structure in a social network. I tried this on a very small data set (Zachary's Karate club) that was available to me. I am looking out for some…
Nihar Sarangi
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Modifying Normalized Cut algorithm to solve largest eigenvectors instead

I am trying to implement Normalized Cut Algorithm . In the original paper (Shi & Malik), they compute the k smallest eigenvectors of: (D-W)x = lambda Dx which is equivalent to solving: D^(-1/2) (D-W) D^(-1/2) x = lambda x D being a diagonal…
haganov
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Vim errorformat and spectral lint

I am attempting to define an error format for the Spectral OpenAPI linter (https://github.com/stoplightio/spectral). The code I have is below, but what I'm seeing is that after I run :make the quickfix window populates with lines from Spectral, but…
Michael
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import error when using spafe library for feature extraction

I ' am working on audio file and need to use spafe library for lfcc, lpc... and i install the library as mentionned in the site : https://spafe.readthedocs.io/en/latest/ But when i try to extract some features , like lfcc, mfcc, lpc, i have import…
BARRY
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Matching peaks in similar spectra in python

I have a series of many thousands of (1D) spectra corresponding to different repetitions of an experiment. For each repetition, the same data has been recorded by two different instruments - so I have two very similar spectra, each consisting of a…
fempi
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Plotting spectral data in one plot using R

I'm having multiple data frames where the first column (in the end filled with NA's) is the wavenumber and the other columns are my variables of the specific wavenumber for multiple observations. Is there a possibility to plot the columns in a way…
Capt.Krusty
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Matlab: going from spectral density to variance

I am trying to understand the relationship between the spectral density of a time series and its variance. From what I understand, the integral of the spectral density should be equal to the variance. At least according to most lecture notes such…
user3452436
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Creating Spectral Heat maps or Intensity maps from CDIP data using Ruby

BACKGROUND Per the Coastal Information Data Program (CDIP), they are generating a spectral heat/intensity map for wave swell at…
Chip Castle
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FWHM calculation using python

I am trying to calculate the FWHM of spectra using python. The spectral description (I'm talking in terms of the physics) for me it's bit complicated and I can't fit the data using some simple Gaussian or Lorentizian profile. So far I managed to…
Shubhadip Chakraborty
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How to cluster a given sample to class centers calculated by spectral clustering algorithm?

Suppose we got several centers {C1(d1, d2...dn), C2...} with training samples according to spectral clustering algorithm. If a new test sample vector (x1, ... xn) is given, what should I do to get it into a class? Note that, the similarity matrix we…
Potemkin
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How to iteratively load read_pixel and write to envi file; python3

I want to load hyperspectral data per pixel into an array and write this pixel out again using Python 3.5. I want to calculate something with the spectral information of this Pixel. I have tried two different ways and both don't work the way I…
AnneR
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Spectral clustering on sparse dataset

I am applying spectral clustering (sklearn.cluster.SpectralClustering) on a dataset with quite some features that are relatively sparse. When doing spectral clustering in Python, I get the following warning: UserWarning: Graph is not fully…
Guido
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Harmonic fit sometimes upside down in R

My first post so apologies for any mistakes. I'm attempting to perform spectral analysis on a simulated circadian data set. I'm splitting the dataset into overlapping windows of say 72 hours, moving the window by 1 hour at a time then performing…
outb4break
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