version 1.4, 2010/08/06 15:32:36
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version 1.9, 2011/07/22 07:38:12
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SUBROUTINE DTGEXC( WANTQ, WANTZ, N, A, LDA, B, LDB, Q, LDQ, Z, |
SUBROUTINE DTGEXC( WANTQ, WANTZ, N, A, LDA, B, LDB, Q, LDQ, Z, |
$ LDZ, IFST, ILST, WORK, LWORK, INFO ) |
$ LDZ, IFST, ILST, WORK, LWORK, INFO ) |
* |
* |
* -- LAPACK routine (version 3.2) -- |
* -- LAPACK routine (version 3.3.1) -- |
* -- LAPACK is a software package provided by Univ. of Tennessee, -- |
* -- LAPACK is a software package provided by Univ. of Tennessee, -- |
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
* November 2006 |
* -- April 2011 -- |
* |
* |
* .. Scalar Arguments .. |
* .. Scalar Arguments .. |
LOGICAL WANTQ, WANTZ |
LOGICAL WANTQ, WANTZ |
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* DTGEXC reorders the generalized real Schur decomposition of a real |
* DTGEXC reorders the generalized real Schur decomposition of a real |
* matrix pair (A,B) using an orthogonal equivalence transformation |
* matrix pair (A,B) using an orthogonal equivalence transformation |
* |
* |
* (A, B) = Q * (A, B) * Z', |
* (A, B) = Q * (A, B) * Z**T, |
* |
* |
* so that the diagonal block of (A, B) with row index IFST is moved |
* so that the diagonal block of (A, B) with row index IFST is moved |
* to row ILST. |
* to row ILST. |
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* Optionally, the matrices Q and Z of generalized Schur vectors are |
* Optionally, the matrices Q and Z of generalized Schur vectors are |
* updated. |
* updated. |
* |
* |
* Q(in) * A(in) * Z(in)' = Q(out) * A(out) * Z(out)' |
* Q(in) * A(in) * Z(in)**T = Q(out) * A(out) * Z(out)**T |
* Q(in) * B(in) * Z(in)' = Q(out) * B(out) * Z(out)' |
* Q(in) * B(in) * Z(in)**T = Q(out) * B(out) * Z(out)**T |
* |
* |
* |
* |
* Arguments |
* Arguments |
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* On exit, the updated matrix A, again in generalized |
* On exit, the updated matrix A, again in generalized |
* real Schur canonical form. |
* real Schur canonical form. |
* |
* |
* LDA (input) INTEGER |
* LDA (input) INTEGER |
* The leading dimension of the array A. LDA >= max(1,N). |
* The leading dimension of the array A. LDA >= max(1,N). |
* |
* |
* B (input/output) DOUBLE PRECISION array, dimension (LDB,N) |
* B (input/output) DOUBLE PRECISION array, dimension (LDB,N) |
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* On exit, the updated matrix B, again in generalized |
* On exit, the updated matrix B, again in generalized |
* real Schur canonical form (A,B). |
* real Schur canonical form (A,B). |
* |
* |
* LDB (input) INTEGER |
* LDB (input) INTEGER |
* The leading dimension of the array B. LDB >= max(1,N). |
* The leading dimension of the array B. LDB >= max(1,N). |
* |
* |
* Q (input/output) DOUBLE PRECISION array, dimension (LDZ,N) |
* Q (input/output) DOUBLE PRECISION array, dimension (LDQ,N) |
* On entry, if WANTQ = .TRUE., the orthogonal matrix Q. |
* On entry, if WANTQ = .TRUE., the orthogonal matrix Q. |
* On exit, the updated matrix Q. |
* On exit, the updated matrix Q. |
* If WANTQ = .FALSE., Q is not referenced. |
* If WANTQ = .FALSE., Q is not referenced. |