Hi Rasmus, Actually, `p_null` gets initialized to an empty/nullptr array (in the highest superclass [1]) which then gets converted to a nullptr that the assignment checks for and ignores. I did a quick try by removing it which seems to show it has no effect. However, I only have limited tests.
Thanks, -Edward 1. I had to step through the debugger to find it On Wed, Mar 23, 2022 at 8:15 PM Rasmus Munk Larsen <[email protected]> wrote: > It looks like p_null is uninitialized, so it looks like undefined behavior > to me, but I'm not entirely sure. Did you try to remove *.twistedby(p_null); > ?* > > On Tue, Mar 22, 2022 at 2:03 PM Edward Lam <[email protected]> wrote: > >> Hi, >> >> At >> https://gitlab.com/libeigen/eigen/-/blob/master/Eigen/src/PardisoSupport/PardisoSupport.h#L474 >> (and also at line 538), we have code like this: >> >> void getMatrix(const MatrixType& matrix){ // PARDISO supports only upper, >> row-major matrices PermutationMatrix<Dynamic,Dynamic,StorageIndex> p_null; >> m_matrix.resize(matrix.rows(), matrix.cols()); m_matrix.template >> selfadjointView<Upper>() = matrix.template >> selfadjointView<UpLo>().twistedBy(p_null); m_matrix.makeCompressed();} >> >> As far as I can tell, the call to *twistedBy(p_null)* in the code is a >> no-op right? Or does it serve some purpose that I'm missing? >> >> Thanks, >> -Edward >> >
