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Class org.netlib.lapack.Dorgtr

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

public class Dorgtr

extends Object

Following is the description from the original
Fortran source.  For each array argument, the Java
version will include an integer offset parameter, so
the arguments may not match the description exactly.
Contact seymour@cs.utk.edu with any questions.

 *     ..
 *
 *  Purpose
 *  =======
 *
 *  DORGTR generates a real orthogonal matrix Q which is defined as the
 *  product of n-1 elementary reflectors of order N, as returned by
 *  DSYTRD:
 *
 *  if UPLO = 'U', Q = H(n-1) . . . H(2) H(1),
 *
 *  if UPLO = 'L', Q = H(1) H(2) . . . H(n-1).
 *
 *  Arguments
 *  =========
 *
 *  UPLO    (input) CHARACTER*1
 *          = 'U': Upper triangle of A contains elementary reflectors
 *                 from DSYTRD;
 *          = 'L': Lower triangle of A contains elementary reflectors
 *                 from DSYTRD.
 *
 *  N       (input) INTEGER
 *          The order of the matrix Q. N >= 0.
 *
 *  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
 *          On entry, the vectors which define the elementary reflectors,
 *          as returned by DSYTRD.
 *          On exit, the N-by-N orthogonal matrix Q.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A. LDA >= max(1,N).
 *
 *  TAU     (input) DOUBLE PRECISION array, dimension (N-1)
 *          TAU(i) must contain the scalar factor of the elementary
 *          reflector H(i), as returned by DSYTRD.
 *
 *  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. LWORK >= max(1,N-1).
 *          For optimum performance LWORK >= (N-1)*NB, 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 ..

Dorgtr()

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

 public Dorgtr()

 public static void dorgtr(String uplo,
                           int n,
                           double a[],
                           int _a_offset,
                           int lda,
                           double tau[],
                           int _tau_offset,
                           double work[],
                           int _work_offset,
                           int lwork,
                           intW info)

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