Arguments

A

(input/output) REAL or COMPLEX square array, shape $(:,:)$.
On entry, the matrix $A$.
If UPLO = 'U', the upper triangular part of ${\bf A}$ contains the upper triangular part of the matrix $A$. If UPLO = 'L', the lower triangular part of ${\bf A}$ contains the lower triangular part of the matrix $A$.
On exit:
If JOBZ = 'V', then the columns of A contain the orthonormal eigenvectors of the matrix $A$ in the order of the eigenvalues.
If JOBZ = 'N', then the upper triangle (if UPLO = 'U') or the lower triangle (if UPLO = 'L') of A, including the diagonal, is destroyed.

W

(output) REAL array, shape $(:)$ with $size$(W) $= size$(A,1).
The eigenvalues in ascending order.

JOBZ

Optional (input) CHARACTER(LEN=1).


Default value: 'N'.

UPLO

Optional (input) CHARACTER(LEN=1).


Default value: 'U'.

INFO

Optional (output) INTEGER.


If ${\bf INFO}$ is not present and an error occurs, then the program is terminated with an error message.

References: [1] and [17,9,20].