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Class org.netlib.lapack.Dgeqpf

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

public class Dgeqpf

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
 *  =======
 *
 *  DGEQPF computes a QR factorization with column pivoting of a
 *  real M-by-N matrix A: A*P = 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) DOUBLE PRECISION array, dimension (LDA,N)
 *          On entry, the M-by-N matrix A.
 *          On exit, the upper triangle of the array contains the
 *          min(M,N)-by-N upper triangular matrix R; the elements
 *          below the diagonal, together with the array TAU,
 *          represent the orthogonal matrix Q as a product of
 *          min(m,n) elementary reflectors.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A. LDA >= max(1,M).
 *
 *  JPVT    (input/output) INTEGER array, dimension (N)
 *          On entry, if JPVT(i) .ne. 0, the i-th column of A is permuted
 *          to the front of A*P (a leading column); if JPVT(i) = 0,
 *          the i-th column of A is a free column.
 *          On exit, if JPVT(i) = k, then the i-th column of A*P
 *          was the k-th column of A.
 *
 *  TAU     (output) DOUBLE PRECISION array, dimension (min(M,N))
 *          The scalar factors of the elementary reflectors.
 *
 *  WORK    (workspace) DOUBLE PRECISION array, dimension (3*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(n)
 *
 *  Each H(i) has the form
 *
 *     H = 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).
 *
 *  The matrix P is represented in jpvt as follows: If
 *     jpvt(j) = i
 *  then the jth column of P is the ith canonical unit vector.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

Dgeqpf()

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

 public Dgeqpf()

 public static void dgeqpf(int m,
                           int n,
                           double a[],
                           int _a_offset,
                           int lda,
                           int jpvt[],
                           int _jpvt_offset,
                           double tau[],
                           int _tau_offset,
                           double work[],
                           int _work_offset,
                           intW info)

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