The matrix tag has no wiki summary.
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Covariance matrix explanation
I try to understand and visualize myself covariance matrix.
Supposing I have a matrix A = [ 2 3 4; 5 5 6 ], how do I calculate its covariance matrix, and what is ...
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Can Cholesky outer product version result in negative square roots?
Say A is symmetric positive definite matrix , which means one necessary condition is diagonal entries of A are positive. If I do cholesky factorisation using outer product form, Can there be any ...
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1answer
665 views
understanding FFT2 function of Matlab
I am trying to understand what happen when we take FFT2 of a matrix in a matlab.
first have a look at this simple example,
...
2
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1answer
49 views
Reflection Rotation matrix
I'm doing a rigid body between point clouds using SVD.
Sometimes the routine produces an incorrect rotation matrix with a Determinant=-1, ie a reflection matrix.
Any idea why ?
Is there a valid way ...
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1answer
185 views
Matlab BOC (binary offset carrier)
I am trying to implement a binary offset carrier (BOC) direct sequence spread spectrum scheme in MATLAB. In that scheme, a code $c(t)$ (a binary vector which repeats after a certain number of zeros ...
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vote
1answer
158 views
Apply Low Pass (Smoothing) Filter on a Set of Matrices and Reject Outliers
Given a set of a $ 3 $ by $ 3 $ matrices $ {H}_{i} $.
Each matrix is an Homography matrix.
They are used to stabilize Video Stream.
Yet some of them are outliers which creates "Jumps" in the ...
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2answers
389 views
Shortest geometric distance from surface in 3d dataset?
I have a three-dimensional binary image of a collection of discrete, individual voxels ("seeds") contained in a connected 3-dimensional surface ("skin").
(Like a small fruit, with a surface delineated ...
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2answers
335 views
Why do we deal with the eigenvectors of the autocorrelation instead of the data itself?
How intuitively to understand why eigenvectors of the autocorrelation matrix are used, but eigenvectors of the matrix constructed from temporal samples have no sense and aren't used? For example, in ...
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1answer
1k views
Analytical expression for the eigenvectors of a 3x3 real, symmetric matrix?
I am writing an algorithm that process 3D images based on the local moment of inertia.
I have a 3x3 real symmetric matrix, from which I need to find the eigenvalues. I have found a variety of ...
