[SciPy-user] howto construct matrix A: dot(A.T, A) is positive-definite

dmitrey dmitrey.kroshko@scipy....
Fri Oct 5 07:53:38 CDT 2007


hi all,

howto construct matrix A of shape (m,n): dot(A.T, A) is positive-definite?

I try to translate some matlab code (box-bounded linear least squares) 
to Python, and I constantly get
"LinAlgError: Matrix is not positive definite -         Cholesky 
decomposition cannot be computed"

Maybe it's because I comment those lines of using colmmd func (Sparse 
column    minimum degree permutation)-
can it be the reason?

Thank you in advance for your suggestions, D.



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