Questions tagged [spectral]
145 questions
0
votes
0 answers
spectral-cli instalation in ubuntu getting failed
npm install -g @stoplight/spectral-cli
Giving below error
npm WARN node-fetch@2.6.8 requires a peer of encoding@^0.1.0 but none was installed.
npm ERR! Linux 5.4.0-1094-azure
npm ERR! argv "/usr/bin/node" "/usr/bin/npm" "install" "-g"…
Vowneee
- 956
- 10
- 33
0
votes
0 answers
Interpolation via Fast Discrete Fourier Transform with Chebyshev extreme points
I'm trying to interpolate a function at arbitrary points and I have the function values at Chebyshev extreme points. I use the real values from Fast Fourier Transform to compute the Chebyshev coefficients. Then I scale them with 2/N and then I use…
Kristoffer Lindvall
- 121
- 2
- 11
0
votes
0 answers
White noise test from spectral analysis
What is the white noise test from spectral analysis? In my project I am asked to work on evaluating whether the residual series behave like white noise series by Ljung-Box test and the white-noise test from spectral analysis. I fitted a model using…
0
votes
0 answers
Calculate normalized spectral entropy of time series
I have a time series data
c1= c(0.558642328,
0.567173803,
0.572518969,
0.579917556,
0.592155421,
0.600239837,
0.598955071,
0.608857572,
0.615442061,
0.613502347,
0.618076897,
0.626769781,
0.633930194,
0.645518577,
0.66773088,…
kl40
- 53
- 7
0
votes
0 answers
Spectral Python - No module named 'numpy'
So I am following along with the Spectral python documentation and I have all the required packages and other python dependicies installed yet I keep getting an error that shows:
Traceback (most recent call last):
File…
Edward Wynman
- 363
- 1
- 10
0
votes
2 answers
Replacing values in a numpy array by averaging adjacent values
I have a 3D numpy array
dark = np.array(dark_ref.load())
dark.shape
(100, 384, 249)
I have a list of indices for the second and third dimension
l, r, b = np.where(dark > 9000)
len(r)
1799
len(b)
1799
and I have written this function to replace the…
russj
- 25
- 1
- 6
0
votes
0 answers
Remove background of picture Hyperspectral
I have data data as images taken from the camera hyperspectral. The file will come out in .hdr and .raw format. When opening the image, you must use the envi.open command. The point is that the data_nparr obtained from the raw image has a background…
0
votes
2 answers
Spectroscopic data analysos using ML
I have RF spectra of various samples consisting of 5 components in the frequency range of 10MHz to 1000MHz, 1000-2000MHz and so on. I need to predict one of the component in an unknown sample. can anybody please help me on how to represent the data…
0
votes
0 answers
R: Spectral biclustering produces different clusters every time I run it
I am trying to run spectral biclustering (using the biclust package on R) on a correlation matrix I generated from protein concentration and lifestyle traits. When I run the code, however, I get different results for each time I call the…
0
votes
1 answer
How to impose boundary conditions in the Generalized Weighted Residual Method (Chebyshev Galerkin modal form)
I am working on combining a Generalized Weighted Residual Method with an RK4. The GWRM part decomposed the PDEs to the spectral space where the unknowns are Chebyshev coefficients a_k. However, I'm having difficulty seeing how the boundary…
Kristoffer Lindvall
- 121
- 2
- 11
0
votes
1 answer
Spectral Linting to Check for a Tag Being Present
How can I check for tags being present? I can check for tags having values. For example,
paths[*]..summary
shows me the value of the summary tags that are present:
[
"List all pets",
"Create a pet",
"Info for a specific pet"
]
But I want to…
Michael
- 79
- 7
0
votes
0 answers
How to compute reflectance from an image given a wavelength (python)
I have recently come across a paper entitled, "Portable Multispectral Imaging System Based on Raspberry Pi".
In this work, the authors have presented a low-cost spectral imaging system using a raspberry pi. This is done by light multiplexing…
bellawillrise
- 55
- 1
- 7
0
votes
0 answers
RGB data limits in imshow()
I am trying to explore hyperspectral images and how to open, read and show them. For that I am using Spectral Python (SPy). When I call imshow() I get RGB data limits. What do these limits represent and how are they related to the intensities in the…
Sal_H
- 75
- 1
- 11
0
votes
0 answers
Plot peak shift from LED spectrum
I'm working on a code to track a shift in spectrum of an LED over 100 scans. I import my data as an ASCI file. Using the find_peaks function I can print the peak position for the first scan. My end goal is to plot the peak position vs scan…
ehalp
- 1
0
votes
1 answer
Unable to perform Spectral Angle Mapper (SAM) for target detection on hyperspectral data in python
I am working on hyperspectral satellite imagery and I am trying to implement SAM algorithm on my dataset.I am trying to use spectral_angle and msam functions which are available in spectral python library.
I am using following commands. Dataset…
KHIZER
- 21
- 4