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## Arguments

AB
(input/output) REAL or COMPLEX array, shape with (AB,1) and (AB,2) , where is the number of subdiagonals or superdiagonals in the band and is the order of .
On entry, the upper (if UPLO = 'U') or lower (if UPLO = 'L') triangle of matrix in band storage. The diagonals of are stored in the rows of AB so that the column of is stored in the column of as follows:

On exit, is overwritten by values generated during the reduction of to a tridiagonal matrix . If 'U', the first superdiagonal and the diagonal of are returned in rows and of . If 'L', the diagonal and first subdiagonal of are returned in the first two rows of .

W
(output) REAL array, shape with (W) .
The eigenvalues in ascending order.

UPLO
Optional (input) CHARACTER(LEN=1).

Default value: 'U'.

Z
Optional (output) REAL or COMPLEX square array, shape with (Z,1) .
The columns of Z contain the orthonormal eigenvectors of in the order of the eigenvalues.

INFO
Optional (output) INTEGER.

If is not present and an error occurs, then the program is terminated with an error message.
References: [1] and [17,9,20].

Next: Examples Up: Standard Symmetric Eigenvalue Problems Previous: Purpose   Contents   Index
Susan Blackford 2001-08-19