version 1.9, 2012/12/14 12:30:20
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version 1.13, 2016/08/27 15:34:22
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*> \verbatim |
*> \verbatim |
*> |
*> |
*> DGEQR2 computes a QR factorization of a real m by n matrix A: |
*> DGEQR2 computes a QR factorization of a real m by n matrix A: |
*> A = Q * R. |
*> A = Q * R. The diagonal entries of R are nonnegative. |
*> \endverbatim |
*> \endverbatim |
* |
* |
* Arguments: |
* Arguments: |
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*> On entry, the m by n matrix A. |
*> On entry, the m by n matrix A. |
*> On exit, the elements on and above the diagonal of the array |
*> On exit, the elements on and above the diagonal of the array |
*> contain the min(m,n) by n upper trapezoidal matrix R (R is |
*> contain the min(m,n) by n upper trapezoidal matrix R (R is |
*> upper triangular if m >= n); the elements below the diagonal, |
*> upper triangular if m >= n). The diagonal entries of R are |
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*> nonnegative; the elements below the diagonal, |
*> with the array TAU, represent the orthogonal matrix Q as a |
*> with the array TAU, represent the orthogonal matrix Q as a |
*> product of elementary reflectors (see Further Details). |
*> product of elementary reflectors (see Further Details). |
*> \endverbatim |
*> \endverbatim |
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*> \author Univ. of Colorado Denver |
*> \author Univ. of Colorado Denver |
*> \author NAG Ltd. |
*> \author NAG Ltd. |
* |
* |
*> \date September 2012 |
*> \date November 2015 |
* |
* |
*> \ingroup doubleGEcomputational |
*> \ingroup doubleGEcomputational |
* |
* |
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*> where tau is a real scalar, and v is a real vector with |
*> where tau is a real scalar, and v is a real vector with |
*> v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i), |
*> v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in A(i+1:m,i), |
*> and tau in TAU(i). |
*> and tau in TAU(i). |
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*> |
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*> See Lapack Working Note 203 for details |
*> \endverbatim |
*> \endverbatim |
*> |
*> |
* ===================================================================== |
* ===================================================================== |
SUBROUTINE DGEQR2P( M, N, A, LDA, TAU, WORK, INFO ) |
SUBROUTINE DGEQR2P( M, N, A, LDA, TAU, WORK, INFO ) |
* |
* |
* -- LAPACK computational routine (version 3.4.2) -- |
* -- LAPACK computational routine (version 3.6.0) -- |
* -- 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..-- |
* September 2012 |
* November 2015 |
* |
* |
* .. Scalar Arguments .. |
* .. Scalar Arguments .. |
INTEGER INFO, LDA, M, N |
INTEGER INFO, LDA, M, N |