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Artour


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Active since 2013

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Hello,

I have a problem with covariance matrices that turn non-symmetric and negative definite as a consequence of rounding off errors. I've symmetrized the matrices by

A = (A + A')/2;

However, I haven't been able to correct the negative eigenvalues, and it's very important that the matrices are always non-negative definite. For example, the following method doesn't help:

[V,D] = eig(A);
D = max(D,0);
A = V*D/V;

Can anyone please suggest what can be done here.

Thanks,
Artour

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Non-symmetric and negative definite covariance matrices, as a consequence of rounding off errors
Matt J, thanks for your answer. Unfortunately I can't make the matrix positive definite. I'm looking at a Kalman filtering probl...

12 years ago | 0

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Non-symmetric and negative definite covariance matrices, as a consequence of rounding off errors
Hello, I have a problem with covariance matrices that turn non-symmetric and negative definite, as a consequence of rounding ...

12 years ago | 2 answers | 0

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