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cgeqpf.f(3)                         LAPACK                         cgeqpf.f(3)

NAME
       cgeqpf.f -

SYNOPSIS
   Functions/Subroutines
       subroutine cgeqpf (M, N, A, LDA, JPVT, TAU, WORK, RWORK, INFO)
           CGEQPF

Function/Subroutine Documentation
   subroutine cgeqpf (integerM, integerN, complex, dimension( lda, * )A,
       integerLDA, integer, dimension( * )JPVT, complex, dimension( * )TAU,
       complex, dimension( * )WORK, real, dimension( * )RWORK, integerINFO)
       CGEQPF

       Purpose:

            This routine is deprecated and has been replaced by routine CGEQP3.

            CGEQPF computes a QR factorization with column pivoting of a
            complex M-by-N matrix A: A*P = Q*R.

       Parameters:
           M

                     M is INTEGER
                     The number of rows of the matrix A. M >= 0.

           N

                     N is INTEGER
                     The number of columns of the matrix A. N >= 0

           A

                     A is COMPLEX 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

                     LDA is INTEGER
                     The leading dimension of the array A. LDA >= max(1,M).

           JPVT

                     JPVT is 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

                     TAU is COMPLEX array, dimension (min(M,N))
                     The scalar factors of the elementary reflectors.

           WORK

                     WORK is COMPLEX array, dimension (N)

           RWORK

                     RWORK is REAL array, dimension (2*N)

           INFO

                     INFO is INTEGER
                     = 0:  successful exit
                     < 0:  if INFO = -i, the i-th argument had an illegal value

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           November 2011

       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**H

             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.

             Partial column norm updating strategy modified by
               Z. Drmac and Z. Bujanovic, Dept. of Mathematics,
               University of Zagreb, Croatia.
             -- April 2011                                                      --
             For more details see LAPACK Working Note 176.

       Definition at line 149 of file cgeqpf.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2                   Sat Nov 16 2013                    cgeqpf.f(3)