org.netlib.lapack
Class SGELQ2

java.lang.Object
  org.netlib.lapack.SGELQ2

public class SGELQ2
extends java.lang.Object

SGELQ2 is a simplified interface to the JLAPACK routine sgelq2.
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
 *  =======
 *
 *  SGELQ2 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) REAL 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) REAL array, dimension (min(M,N))
 *          The scalar factors of the elementary reflectors (see Further

 *          Details).
 *
 *  WORK    (workspace) REAL array, dimension (M)
 *
 *  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).
 *
 *  =====================================================================
 *
 *     .. Parameters ..

Constructor Summary

SGELQ2()

Method Summary

static void

SGELQ2(int m, int n, float[][] a, float[] tau, float[] work, intW info)

Methods inherited from class java.lang.Object

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

Constructor Detail

SGELQ2

public SGELQ2()

Method Detail

SGELQ2

public static void SGELQ2(int m,
                          int n,
                          float[][] a,
                          float[] tau,
                          float[] work,
                          intW info)