RWQRCalcP3<T>

Module:  Linear Algebra   Group:  Decomposition classes

Does not inherit

• Local Index
• Synopsis
• Description
• Static Member Function

Members

computeQR()

#include <rw/lapack/qrcalcp3.h>

Computes the QR decomposition of a matrix A using the LAPACK function xgeqp3. This class may be used as the QRCalc template parameter for the classes RWQRDecomp<T,QRCalc>, RWQRDecompServer<T,QRCalc>, RWLeastSqQR<T,QRCalc>, and RWCODecomp<T,QRCalc>.

static bool
computeQR(RWGenMat<T>&    A,
          RWMathVec<T>&   tau,
           long *const      pivots);
static bool
computeQR(RWGenMat<T>&    A,
          RWMathVec<T>&   tau,
           int *const      pivots);

Parameters:

On entry, A is the M-by-N matrix for which the QR decomposition is being computed. On exit, the upper triangle of the array contains the min(M,N)-by-N upper triangular matrix R; the elements below the diagonal, together with the vector tau, represent the orthogonal matrix Q as a product of min(m,n) elementary reflectors.

If pivots != null, then on entry, if pivots[i] != 0, the i-th columnof A is permuted to the front of A*P (a leading column); if pivots(i) == 0, the i-th column of A is a free column. On exit, if pivots[i] = k, then the i-th column of A*P was the k-th column of A. If pivots == null, pivoting is not done..

© Copyright Rogue Wave Software, Inc. All Rights Reserved.
Rogue Wave and SourcePro are registered trademarks of Rogue Wave Software, Inc. in the United States and other countries. All other trademarks are the property of their respective owners.
Contact Rogue Wave about documentation or support issues.