org.netlib.lapack
Class Sgeqr2

java.lang.Object
  org.netlib.lapack.Sgeqr2

public class Sgeqr2
extends java.lang.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
 *  =======
 *
 *  SGEQR2 computes a QR factorization of a real m by n matrix A:
 *  A = Q * R.
 *
 *  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 above the diagonal of the array

 *          contain the min(m,n) by n upper trapezoidal matrix R (R is
 *          upper triangular if m >= n); the elements below 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 (N)
 *
 *  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(1) H(2) . . . H(k), 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:m) is stored on exit in A(i+1:m,i),

 *  and tau in TAU(i).
 *
 *  =====================================================================
 *
 *     .. Parameters ..

Constructor Summary

Sgeqr2()

Method Summary

static void

sgeqr2(int m, int n, float[] a, int _a_offset, int lda, float[] tau, int _tau_offset, float[] work, int _work_offset, intW info)

Methods inherited from class java.lang.Object

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

Constructor Detail

Sgeqr2

public Sgeqr2()

Method Detail

sgeqr2

public static void sgeqr2(int m,
                          int n,
                          float[] a,
                          int _a_offset,
                          int lda,
                          float[] tau,
                          int _tau_offset,
                          float[] work,
                          int _work_offset,
                          intW info)