.TH "SRC/DEPRECATED/dgeqpf.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*-
.ad l
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.SH NAME
SRC/DEPRECATED/dgeqpf.f
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "subroutine \fBdgeqpf\fP (m, n, a, lda, jpvt, tau, work, info)"
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.RI "\fBDGEQPF\fP "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine dgeqpf (integer m, integer n, double precision, dimension( lda, * ) a, integer lda, integer, dimension( * ) jpvt, double precision, dimension( * ) tau, double precision, dimension( * ) work, integer info)"

.PP
\fBDGEQPF\fP  
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\fBPurpose:\fP
.RS 4

.PP
.nf
 This routine is deprecated and has been replaced by routine DGEQP3\&.

 DGEQPF computes a QR factorization with column pivoting of a
 real M-by-N matrix A: A*P = Q*R\&.
.fi
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.RE
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\fBParameters\fP
.RS 4
\fIM\fP 
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          M is INTEGER
          The number of rows of the matrix A\&. M >= 0\&.
.fi
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\fIN\fP 
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          N is INTEGER
          The number of columns of the matrix A\&. N >= 0
.fi
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.br
\fIA\fP 
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.nf
          A is 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\&.
.fi
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\fILDA\fP 
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          LDA is INTEGER
          The leading dimension of the array A\&. LDA >= max(1,M)\&.
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\fIJPVT\fP 
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          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\&.
.fi
.PP
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\fITAU\fP 
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          TAU is DOUBLE PRECISION array, dimension (min(M,N))
          The scalar factors of the elementary reflectors\&.
.fi
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\fIWORK\fP 
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          WORK is DOUBLE PRECISION array, dimension (3*N)
.fi
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\fIINFO\fP 
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          INFO is INTEGER
          = 0:  successful exit
          < 0:  if INFO = -i, the i-th argument had an illegal value
.fi
.PP
 
.RE
.PP
\fBAuthor\fP
.RS 4
Univ\&. of Tennessee 
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Univ\&. of California Berkeley 
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Univ\&. of Colorado Denver 
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NAG Ltd\&. 
.RE
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\fBFurther Details:\fP
.RS 4

.PP
.nf
  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**T

  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\&.

  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\&.
.fi
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.RE
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Definition at line \fB141\fP of file \fBdgeqpf\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.