org.netlib.lapack
Class DORMBR

java.lang.Object
  org.netlib.lapack.DORMBR

public class DORMBR
extends java.lang.Object

DORMBR is a simplified interface to the JLAPACK routine dormbr.
This interface converts Java-style 2D row-major arrays into
the 1D column-major linearized arrays expected by the lower
level JLAPACK routines.  Using this interface also allows you
to omit offset and leading dimension arguments.  However, because
of these conversions, these routines will be slower than the low
level ones.  Following is the description from the original Fortran
source.  Contact seymour@cs.utk.edu with any questions.

 *     ..
 *
 *  Purpose
 *  =======
 *
 *  If VECT = 'Q', DORMBR overwrites the general real M-by-N matrix C
 *  with
 *                  SIDE = 'L'     SIDE = 'R'
 *  TRANS = 'N':      Q * C          C * Q
 *  TRANS = 'T':      Q**T * C       C * Q**T
 *
 *  If VECT = 'P', DORMBR overwrites the general real M-by-N matrix C
 *  with
 *                  SIDE = 'L'     SIDE = 'R'
 *  TRANS = 'N':      P * C          C * P
 *  TRANS = 'T':      P**T * C       C * P**T
 *
 *  Here Q and P**T are the orthogonal matrices determined by DGEBRD when
 *  reducing a real matrix A to bidiagonal form: A = Q * B * P**T. Q and

 *  P**T are defined as products of elementary reflectors H(i) and G(i)
 *  respectively.
 *
 *  Let nq = m if SIDE = 'L' and nq = n if SIDE = 'R'. Thus nq is the
 *  order of the orthogonal matrix Q or P**T that is applied.
 *
 *  If VECT = 'Q', A is assumed to have been an NQ-by-K matrix:
 *  if nq >= k, Q = H(1) H(2) . . . H(k);
 *  if nq < k, Q = H(1) H(2) . . . H(nq-1).
 *
 *  If VECT = 'P', A is assumed to have been a K-by-NQ matrix:
 *  if k < nq, P = G(1) G(2) . . . G(k);
 *  if k >= nq, P = G(1) G(2) . . . G(nq-1).
 *
 *  Arguments
 *  =========
 *
 *  VECT    (input) CHARACTER*1
 *          = 'Q': apply Q or Q**T;
 *          = 'P': apply P or P**T.
 *
 *  SIDE    (input) CHARACTER*1
 *          = 'L': apply Q, Q**T, P or P**T from the Left;
 *          = 'R': apply Q, Q**T, P or P**T from the Right.
 *
 *  TRANS   (input) CHARACTER*1
 *          = 'N':  No transpose, apply Q  or P;
 *          = 'T':  Transpose, apply Q**T or P**T.
 *
 *  M       (input) INTEGER
 *          The number of rows of the matrix C. M >= 0.
 *
 *  N       (input) INTEGER
 *          The number of columns of the matrix C. N >= 0.
 *
 *  K       (input) INTEGER
 *          If VECT = 'Q', the number of columns in the original
 *          matrix reduced by DGEBRD.
 *          If VECT = 'P', the number of rows in the original
 *          matrix reduced by DGEBRD.
 *          K >= 0.
 *
 *  A       (input) DOUBLE PRECISION array, dimension
 *                                (LDA,min(nq,K)) if VECT = 'Q'
 *                                (LDA,nq)        if VECT = 'P'
 *          The vectors which define the elementary reflectors H(i) and
 *          G(i), whose products determine the matrices Q and P, as
 *          returned by DGEBRD.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A.
 *          If VECT = 'Q', LDA >= max(1,nq);
 *          if VECT = 'P', LDA >= max(1,min(nq,K)).
 *
 *  TAU     (input) DOUBLE PRECISION array, dimension (min(nq,K))
 *          TAU(i) must contain the scalar factor of the elementary
 *          reflector H(i) or G(i) which determines Q or P, as returned
 *          by DGEBRD in the array argument TAUQ or TAUP.
 *
 *  C       (input/output) DOUBLE PRECISION array, dimension (LDC,N)
 *          On entry, the M-by-N matrix C.
 *          On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or C*Q
 *          or P*C or P**T*C or C*P or C*P**T.
 *
 *  LDC     (input) INTEGER
 *          The leading dimension of the array C. LDC >= max(1,M).
 *
 *  WORK    (workspace/output) DOUBLE PRECISION array, dimension (LWORK)

 *          On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
 *
 *  LWORK   (input) INTEGER
 *          The dimension of the array WORK.
 *          If SIDE = 'L', LWORK >= max(1,N);
 *          if SIDE = 'R', LWORK >= max(1,M).
 *          For optimum performance LWORK >= N*NB if SIDE = 'L', and
 *          LWORK >= M*NB if SIDE = 'R', where NB is the optimal
 *          blocksize.
 *
 *          If LWORK = -1, then a workspace query is assumed; the routine
 *          only calculates the optimal size of the WORK array, returns
 *          this value as the first entry of the WORK array, and no error
 *          message related to LWORK is issued by XERBLA.
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit
 *          < 0:  if INFO = -i, the i-th argument had an illegal value
 *
 *  =====================================================================
 *
 *     .. Local Scalars ..

Constructor Summary

DORMBR()

Method Summary

static void

DORMBR(java.lang.String vect, java.lang.String side, java.lang.String trans, int m, int n, int k, double[][] a, double[] tau, double[][] c, double[] work, int lwork, intW info)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DORMBR

public DORMBR()

Method Detail

DORMBR

public static void DORMBR(java.lang.String vect,
                          java.lang.String side,
                          java.lang.String trans,
                          int m,
                          int n,
                          int k,
                          double[][] a,
                          double[] tau,
                          double[][] c,
                          double[] work,
                          int lwork,
                          intW info)