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Questions tagged [eigenvalue]

The eigenvalue is the factor by which the eigenvector is scaled when multiplied by the matrix.

The eigenvectors of a square matrix are the non-zero vectors that, after being multiplied by the matrix, remain parallel to the original vector. For each eigenvector, the corresponding eigenvalue is the factor by which the eigenvector is scaled when multiplied by the matrix. The prefix eigen- is adopted from the German word "eigen" for "own"[1] in the sense of a characteristic description. The eigenvectors are sometimes also called characteristic vectors. Similarly, the eigenvalues are also known as characteristic values.

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Power iteration for eigenvectors decomposition - python

All I found about power method, was for the largest/smallest eigenvectors and eigenvalues. How can I compute all eigenvectors of a matrix ? specifically, I'm trying to do that in python, but any resource regarding how to do that would be of great…
matlabit
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How to get real eigenvectors and eigenvalues using Python numpy library?

I am using numpy python library to calculate eigenvalues and eigenvectors of a asymmetric matrix. The eigenvalues i am getting are complex values and corresponding eigenvectors also consist of complex values. Is there any possible way to get real…
Neeraj Sharma
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projection eigenvector space matlab

Hi have a matrix A containing 132 elements of 3 features each A= rand(132,3); I compute the distance between each element B=pdist(A); and I put it in a squared distance matrix C = squareform(B); I compute the eigenvectors of the matrix [V,D] =…
gabboshow
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getting a segfault coredump when restarting the Lanczos method after 3 iterations

So I'm working on the convergence of Lanczos algorithm. I implemented it in C language, I first calculate both the matrix V which is the orthonormal associated to the Krylov subspace, and the Triadiagonal symetric matrix T, after that I compute the…
Adil
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Adjacency uint8 sparse eigenvalues

I have a source and target matrix which I'm creating an adjacency matrix using sparse function. W = sparse(w1(:,1),w1(:,2),1,n,n); my n is approximately equal to 540,000 (this is a subset of the data I have). Creating the matrix itself is pretty…
Paulo Quinderé Saraiva
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How to see the error as a function of iteration steps in eigs()

I am using [Evec,Eval]=eigs(H,1,’sa’) in Matlab to compute the smallest eigenvalue of a sparse matrix H. Can I get the error of the smallest eigenvalue as a function of iteration step?
Timothy
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OpenCV Prediction

Good evening everyone, I have tried to use this Keep in my that my Ptr variable is of type BasicFaceRecognizer as per OpenCV 3.0 documentation: http://docs.opencv.org/master/db/d7c/group__face.html#gsc.tab=0 Ptr model; int…
Chris
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Eigen Value Solver for Graph

Say I have a graph with 10 million nodes and 100 million edges. I would like to compute the largest Eigen value on the adjacency matrix of this graph. Which Eigen value solvers should work for the graph this big. Note that the matrix is sparse.
max
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Armadillo: eigs_gen can not successfully give answer

I'm using armadillo's eigs_gen to find the smallest algebraic eigenvalue of a sparse matrix, but eigs_gen can not give an answer. I test the eigs_gen for eye matrix 6*6, it also can not give the answer. The code is: #include #include…
Hen Xue
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Matlab place function error

Interesting problem here. On our school's Windows server, Matlab can execute the place function in the following code perfectly well and return a 1x4 matrix assigned to variable K. However, the Linux servers, and Matlab on my personal computer…
michael_e
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Different ways to check whether an eigenvalue equals a real number?

I have the following matrix M <- structure(c(0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0), .Dim = c(5L, 5L)) I want to find the eigenvalues that are exactly 1. I thought this would work: Re(eigen(M)$values) == 1 &…
Heisenberg
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opencv error Assertion failed Mat.cpp line: 537

I am trying to find the eigenvalues and eigenvectors a matrix as shown below: int m = 5; float b[5][5] = { { 1.96 , -6.49, -0.47, -7.20, -0.65}, { -6.49, 3.80, -6.39, 1.50, -6.34}, { -0.47, -6.39, 4.17, -1.51, 2.67}, { -7.20, …
raghuram
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Spectral clustering with Similarity matrix constructed by jaccard coefficient

I have a categorical dataset, I am performing spectral clustering on it. But I do not get very good output. I choose the eigen vectors corresponding to largest eigen values as my centroids for k-means. Please find below the process I follow: 1.…
Sam
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Matlab calculations of major/minor axis lengths (regiosprops)

I have been doing a fair bit of searching around for an answer to my issue here.. hopefully someone can tell me where im going wrong. im trying to replicate matlabs regionprops function to calculate major/minor axis lengths, and think i understand…
James Mapp
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How to find and plot eigenvalues of symbolic 6*6 matrix

I have a symbolic 6x6 matrics that I must find eigenvalues and plot them. I can't plot and I don't know what can I do. syms t H t1 t2 E1 E2 E3 E4 E5 E6 HH H1 v d H2 k a E; t1=1; t2=1.5*t1; a=3; H=[0 t2 0 0 0 t1 t2 0 t1 0 0 0 0 t1 0…
N Naghdiani
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