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Class org.netlib.lapack.Dgelqf

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

public class Dgelqf

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
 *  =======
 *
 *  DGELQF computes an LQ factorization of a real M-by-N matrix A:
 *  A = L * Q.
 *
 *  Arguments
 *  =========
 *
 *  M       (input) INTEGER
 *          The number of rows of the matrix A.  M >= 0.
 *
 *  N       (input) INTEGER
 *          The number of columns of the matrix A.  N >= 0.
 *
 *  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
 *          On entry, the M-by-N matrix A.
 *          On exit, the elements on and below the diagonal of the array
 *          contain the m-by-min(m,n) lower trapezoidal matrix L (L is
 *          lower triangular if m <= n); the elements above the diagonal,
 *          with the array TAU, represent the orthogonal matrix Q as a
 *          product of elementary reflectors (see Further Details).
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A.  LDA >= max(1,M).
 *
 *  TAU     (output) DOUBLE PRECISION array, dimension (min(M,N))
 *          The scalar factors of the elementary reflectors (see Further
 *          Details).
 *
 *  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,M).
 *          For optimum performance LWORK >= M*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
 *
 *  Further Details
 *  ===============
 *
 *  The matrix Q is represented as a product of elementary reflectors
 *
 *     Q = H(k) . . . H(2) H(1), where k = min(m,n).
 *
 *  Each H(i) has the form
 *
 *     H(i) = I - tau * v * v'
 *
 *  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:n) is stored on exit in A(i,i+1:n),
 *  and tau in TAU(i).
 *
 *  =====================================================================
 *
 *     .. Local Scalars ..

Dgelqf()

dgelqf(int, int, double[], int, int, double[], int, double[], int, int, intW)

 public Dgelqf()

 public static void dgelqf(int m,
                           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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