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Class org.netlib.lapack.Dgeqrs

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

public class Dgeqrs

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
 *  =======
 *
 *  Solve the least squares problem
 *      min || A*X - B ||
 *  using the QR factorization
 *      A = Q*R
 *  computed by DGEQRF.
 *
 *  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.  M >= N >= 0.
 *
 *  NRHS    (input) INTEGER
 *          The number of columns of B.  NRHS >= 0.
 *
 *  A       (input) DOUBLE PRECISION array, dimension (LDA,N)
 *          Details of the QR factorization of the original matrix A as
 *          returned by DGEQRF.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A.  LDA >= M.
 *
 *  TAU     (input) DOUBLE PRECISION array, dimension (N)
 *          Details of the orthogonal matrix Q.
 *
 *  B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS)
 *          On entry, the m-by-nrhs right hand side matrix B.
 *          On exit, the n-by-nrhs solution matrix X.
 *
 *  LDB     (input) INTEGER
 *          The leading dimension of the array B. LDB >= M.
 *
 *  WORK    (workspace) DOUBLE PRECISION array, dimension (LWORK)
 *
 *  LWORK   (input) INTEGER
 *          The length of the array WORK.  LWORK must be at least NRHS,
 *          and should be at least NRHS*NB, where NB is the block size
 *          for this environment.
 *
 *  INFO    (output) INTEGER
 *          = 0: successful exit
 *          < 0: if INFO = -i, the i-th argument had an illegal value
 *
 *  =====================================================================
 *
 *     .. Parameters ..

Dgeqrs()

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

 public Dgeqrs()

 public static void dgeqrs(int m,
                           int n,
                           int nrhs,
                           double a[],
                           int _a_offset,
                           int lda,
                           double tau[],
                           int _tau_offset,
                           double b[],
                           int _b_offset,
                           int ldb,
                           double work[],
                           int _work_offset,
                           int lwork,
                           intW info)

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