LAPACK/ScaLAPACK Development

I got this message, what's the problem in my program?? How can I solve it ??

Thank you very much!

My program is written in f95 code, does it create trouble??

Could you give your calling sequence?
It seems that the 4th parameter: SENSE is wrong.

From the routine:

* SENSE (input) CHARACTER*1
* Determines which reciprocal condition numbers are computed.
* = 'N': None are computed;
* = 'E': Computed for eigenvalues only;
* = 'V': Computed for right eigenvectors only;
* = 'B': Computed for eigenvalues and right eigenvectors.
*
* If SENSE = 'E' or 'B', both left and right eigenvectors
* must also be computed (JOBVL = 'V' and JOBVR = 'V').

Checke especially the last condition if SENSE 'E' or 'B'. Are JOBVL and JOBVR set to 'V'?

Julie

This is my calling sequence

CALL DGEEVX( 'N', 'N', 'N', 'E', n, A, n, Er, Ei, &
UL, LDVL, UR, LDVR, ILO, IHI, SCALE, ABNRM, &
RCONDE, RCONDV, WORK, LWORK, IWORK, INFO )

I am going to compute the eigenvalues, so it should be 'E', right ???

* If SENSE = 'E' or 'B', both left and right eigenvectors
* must also be computed (JOBVL = 'V' and JOBVR = 'V').

So you want

Code: Select all

CALL DGEEVX( 'N', 'V', 'V', 'E', ... )


oh, I see, I missed this information, thank you very much
Let me try it again

By the way, I am going to solve the eigenvalues of a second order differential equation

thus I solve the eigenvalues of the finite differencing matrix

the matrix is tridiagonal, but not symmetric

I have searched through the list of routines of LAPACK

I cannot find routines for solving non-symmetric tridiagonal matrix

I want to know if there are any solvers that can solve the eigenvalues of a non-symmetric tridiagonal matrix

Thank you very much