Dear all,
I want to compute eigenvalues and eigenvectors of a matrix already in the upper Hessenberg form. I see that the PDLAHQR routine in scaLAPACK computes eigenvalues and Schur vectors of a hessenberg matrix.
So, i want to know if Schur vectors represents eigenvectors ? if it isn't the case is there other routine in scaLAPACK which computes eigenvalues and eigenvectors of a hessenberg matrix?
Finally, if schur vectors represents eigenvectors, should i before calling the PDLAHQR routine do a call to the PDHSEQR routine to compute the matrix Z from the Schur decomposition?
Thank you in advance for your help.
Best regards
Makarem