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Class org.netlib.lapack.DORMQR

java.lang.Object
   |
   +----org.netlib.lapack.DORMQR

public class DORMQR

extends Object

DORMQR is a simplified interface to the JLAPACK routine dormqr.
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
 *  =======
 *
 *  DORMQR 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
 *
 *  where Q is a real orthogonal matrix defined as the product of k
 *  elementary reflectors
 *
 *        Q = H(1) H(2) . . . H(k)
 *
 *  as returned by DGEQRF. Q is of order M if SIDE = 'L' and of order N
 *  if SIDE = 'R'.
 *
 *  Arguments
 *  =========
 *
 *  SIDE    (input) CHARACTER*1
 *          = 'L': apply Q or Q**T from the Left;
 *          = 'R': apply Q or Q**T from the Right.
 *
 *  TRANS   (input) CHARACTER*1
 *          = 'N':  No transpose, apply Q;
 *          = 'T':  Transpose, apply Q**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
 *          The number of elementary reflectors whose product defines
 *          the matrix Q.
 *          If SIDE = 'L', M >= K >= 0;
 *          if SIDE = 'R', N >= K >= 0.
 *
 *  A       (input) DOUBLE PRECISION array, dimension (LDA,K)
 *          The i-th column must contain the vector which defines the
 *          elementary reflector H(i), for i = 1,2,...,k, as returned by
 *          DGEQRF in the first k columns of its array argument A.
 *          A is modified by the routine but restored on exit.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A.
 *          If SIDE = 'L', LDA >= max(1,M);
 *          if SIDE = 'R', LDA >= max(1,N).
 *
 *  TAU     (input) DOUBLE PRECISION array, dimension (K)
 *          TAU(i) must contain the scalar factor of the elementary
 *          reflector H(i), as returned by DGEQRF.
 *
 *  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.
 *
 *  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.
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit
 *          < 0:  if INFO = -i, the i-th argument had an illegal value
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DORMQR()

DORMQR(String, String, int, int, int, double[][], double[], double[][], double[], int, intW)

 public DORMQR()

 public static void DORMQR(String side,
                           String trans,
                           int m,
                           int n,
                           int k,
                           double a[][],
                           double tau[],
                           double c[][],
                           double work[],
                           int lwork,
                           intW info)

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