### Eigen systems

Posted:

**Thu Jul 21, 2005 1:12 pm**Hi all,

I am completely new to LAPACK. I am trying to find eigen values and eigen vectors for a 4x4 real, non-symmetric matrix. Can some one please answer the following questions?

(1) What is the difference between different drivers: simple vs. expert vs. divide-and-conquer vs. RRR driver? Do the drivers differ in terms of accuracy or they differ in terms of the performance time?

(2) When I input the matrix to the subroutine DGEEV or DGEEVX, it is returning me the left eigen vectors into right and vice versa, similarly rows into columns. I am using CLAPACK Version 3 with Microsoft Visual C++ 6 on Pentium 4 laptop. Can some one help me to resolve this?

Thanks,

mmgk

I am completely new to LAPACK. I am trying to find eigen values and eigen vectors for a 4x4 real, non-symmetric matrix. Can some one please answer the following questions?

(1) What is the difference between different drivers: simple vs. expert vs. divide-and-conquer vs. RRR driver? Do the drivers differ in terms of accuracy or they differ in terms of the performance time?

(2) When I input the matrix to the subroutine DGEEV or DGEEVX, it is returning me the left eigen vectors into right and vice versa, similarly rows into columns. I am using CLAPACK Version 3 with Microsoft Visual C++ 6 on Pentium 4 laptop. Can some one help me to resolve this?

Thanks,

mmgk