zgeqpf(l) [redhat man page]

ZGEQPF(l)								 )								 ZGEQPF(l)

NAME

       ZGEQPF - routine is deprecated and has been replaced by routine ZGEQP3

SYNOPSIS

       SUBROUTINE ZGEQPF( M, N, A, LDA, JPVT, TAU, WORK, RWORK, INFO )

	   INTEGER	  INFO, LDA, M, N

	   INTEGER	  JPVT( * )

	   DOUBLE	  PRECISION RWORK( * )

	   COMPLEX*16	  A( LDA, * ), TAU( * ), WORK( * )

PURPOSE

       This  routine  is deprecated and has been replaced by routine ZGEQP3.  ZGEQPF computes a QR factorization with column pivoting of a complex
       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) COMPLEX*16 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 unitary 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 col-
	       umn 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) COMPLEX*16 array, dimension (min(M,N))
	       The scalar factors of the elementary reflectors.

       WORK    (workspace) COMPLEX*16 array, dimension (N)

       RWORK   (workspace) DOUBLE PRECISION array, dimension (2*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 complex scalar, and v is a complex 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.

LAPACK version 3.0						   15 June 2000 							 ZGEQPF(l)