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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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How to calculate eigenvalues in paraview using python?

I have a cell data F that is an array of 3x3 matrices. How can I calculate the sqrt(eigenvalues of F*F.T matrices) and afterwards append this new cell data? Update 1: This is my code. It does not work because of the line C = F.Arrays[0] *…
Caslu
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eigendecomposition(A = V.D. V^-1) of symmetric matrix in Matlab

Hi I want to compute eig-decomposition of symmetric matrix A in matlab. assume that A = V.D. V^-1(standard form ). I checked eig(A) and svd(A) but svd give me A = U.s.V which U and V are not orthonormal (U.V != I). and also there is a…
Captain
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PSD matrices with identical diagonal elements

How to construct two positive semi definite matrices with identical diagonal elements? Suppose M1 and M2 are tow psd matrices. I want vectors of diagonal( M1 ) and diagonal( M2 ) to be identical. Off-diagonal elements have to be different. [a e f…
Sarbojit Roy
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Matlab gives me negative eigenvalue for positive matrix

I have a 6000*6000 symmetric matrix and all entries are positive. I use eig function of matlab to decompose its eigenvalues&eigenvectors. But there are negative eigenvalues in results. Where do you think is the problem? Thanks. Sevil.
Sevil95
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Eigenvector Order in R

I am trying to work out an issue regarding the order of eigenvectors returned by eigen in r. Consider the following: covmatrix <- matrix(data = c(13, 5, 2, 4), nrow = 2, ncol = 2) covmatrix eigen <- eigen(covmatrix) eigen The output…
user6806805
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how can i find "smallest eigenvalue" o a plate with python scripting in abaqus?

i write a python script to modeling and analysis a plate for buckling. i need the minimum eigenvalue for run the other script for RIKS analysis. how can i find "smallest eigenvalue" with python scripting in abaqus?
ham moa
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Not getting the correct EigenValue/EigenVector (eigenVV)

I'm trying to figure out how to use eigenVV, but no luck so far. The following is my code and could anyone of you point out what I'm doing wrong? Thanks. CvMat* A2; A2 = cvCreateMat(3, 3, CV_32FC1); cvmSet(A2, 0, 0, 1); cvmSet(A2, 0, 1,…
user3273345
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Matlab - find dominant poles programmatically

I have a SISO system (in tf form) with 48 eigenvalues and I want to find the dominant poles (let's say to reduce it to a 1st or 2nd order). I need to know them to approximately calculate damping and bandwidth of my system. I would like not to rely…
Benedetto Roda
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scipy / numpy linalg.eigval result interpretation

I am a newbie when it comes to using python libraries for numerical tasks. I was reading a paper on LexRank and wanted to know how to compute eigenvectors of a transition matrix. I used the eigval function and got a result that I have a hard time…
Vikram Murthy
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Armadillo function eig_sym() not working

I am trying to find the eigenvalues of a square matrix using the function eig_sym from the Armadillo linear algebra library: mat STRESS = Mat(3, 3, fill::zeros); vec principals; /** Populate STRESS with symmetric values from a stress…
Louis Vallance
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Find the eigenvalues of a generic matrix with R

does anyone of you knows a way to use R so to calculate and display the characteristic polynomial of the eigenvalues of a generic matrix composed by chr elements? say i.e. m <- matrix(c('a','b','c','d','e','f','g','h','i','l','m','n'),4,4) Please…
Shatz
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Spectral decomposition (eigen)

i have a problem with calculation the Spectral decomposition, i guess, with the sorting of eigen. According to this website http://www.deltaquants.com/cleaning-correlation-matrices.html i would like to do the same calculation in R Input <-…
meck373
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Get eigenvalue from image with openCV

I'm already done some step for get eigenvalue. the step i have already done is get matrix from image and get average. and now, i must get the transpose of matrix. i don't know why my source code is wrong. anyone could help?? please
huhuhu
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Most positive eigenvalue and corresponding eigenvector of a real symmetric matrix

Is there any way to compute the most positive eigenvalue and eigenvector using power method? Illustrated as follows, for example, let | 1 0 0 | A= | 0 -4 0 | | 0 0 3 | whose eigenvalues are apparently 1, -4 and 3. When I apply power method…
lvamsi
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Eigenvalues computed from R different from other statistical packages and literature results

I am detecting Multicollinearity using eigen values and vector for longley data. When I compute eigen values from SPSS I found different eigen values than R language. I don't why. I computed for both Standardized X matrix and actual X matrix but…
itfeature.com
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