Re: [deal.II] log of a symmetric positive definite tensor

2019-10-15 Thread Wolfgang Bangerth
On 10/15/19 5:17 PM, Maien Hamed wrote: > > But this is not reliable, as I've run into situations where the returned > eigenvalues are fewer than `dim` (I'm not sure how > `compute_eigenvalues_symmetric` treats repeated eigenvalues). I've looked at > using `compute_svd`, but it seems to me that

[deal.II] log of a symmetric positive definite tensor

2019-10-15 Thread Maien Hamed
Hello everyone, Is there a reliable way to get the natural logarithm of a symmetric positive definite tensor in deal.ii? I'm trying `LAPACKFullMatrix.compute_eigenvalues_symmetric`, taking the `std::log` of the eigenvalues and then multiplying by the eigenvectors appropriately: const Symmetric