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## Arguments

A
(input/output) REAL or COMPLEX square array, shape .
On entry, the matrix .
On exit, the Schur form .

w
(output) REAL or COMPLEX array, shape with .
The computed eigenvalues in the order in which they appear on the diagonal of the Schur form . ::= WR(:), WI(:) W(:),
where
WR(:), WI(:) are of REAL type (for the real and imaginary parts) and W(:) is of COMPLEX type.
Note: If is real, then a complex-conjugate pair appear consecutively, with the eigenvalue having the positive imaginary part appearing first.

VS
Optional (output) REAL or COMPLEX square array, shape with (VS,1) (A,1).
The matrix of Schur vectors.

SELECT
Optional (input) LOGICAL FUNCTION
LOGICAL FUNCTION SELECT( w )
type(wp), INTENT(IN) :: w where
type ::= REAL COMPLEX
wp ::= KIND(1.0) KIND(1.0D0)
w ::= WR , WI  W  Note: Select must be present if SDIM, RCONDE and RCONDF are desired.

SDIM
Optional (output) INTEGER.
The number of eigenvalues (after sorting) for which SELECT .TRUE. (If is real, complex conjugate pairs for which SELECT .TRUE. for either eigenvalue count as 2).

RCONDE
Optional (output) REAL.
The reciprocal condition number for the average of the selected eigenvalues.

RCONDV
Optional (output) REAL.
The reciprocal condition number for the selected right invariant subspace.

INFO
Optional (output) INTEGER. If is not present and an error occurs, then the program is terminated with an error message.

References:  and [17,9,20,21].     Next: Example (from Program LA_GEESX_EXAMPLE) Up: Standard Nonsymmetric Eigenvalue Problems Previous: Purpose   Contents   Index
Susan Blackford 2001-08-19