Greetings. I am using the LAPACK (Linear Algebra Package) software package to find the eigenvalues and eigenvectors of a large symmetrical real matrix. Specifically, I calculate a scalar from each eigenvector, and I want to graph it against its associated eigenvalue.(adsbygoogle = window.adsbygoogle || []).push({});

I am using the subroutine DSYEV of LAPACK to do this. However, DSYEV outputs the eigenvalues in ascending order, and I'm not sure how it orders the eigenvectors. Is there a way to associate each eigenvector with its eigenvalue?

Edit: The official page for DSYEV is here: http://www.netlib.org/lapack/double/dsyev.f

Here is another page about it: http://www.nag.co.uk/numeric/fl/nagdoc_fl22/xhtml/F08/f08faf.xml

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# Fortran90: Subroutine DSYEV and associating eigenvalues and eigenvectors.

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