#include "blaswrap.h"
/* zqpt01.f -- translated by f2c (version 20061008).
   You must link the resulting object file with libf2c:
	on Microsoft Windows system, link with libf2c.lib;
	on Linux or Unix systems, link with .../path/to/libf2c.a -lm
	or, if you install libf2c.a in a standard place, with -lf2c -lm
	-- in that order, at the end of the command line, as in
		cc *.o -lf2c -lm
	Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,

		http://www.netlib.org/f2c/libf2c.zip
*/

#include "f2c.h"

/* Table of constant values */

static integer c__10 = 10;
static integer c__1 = 1;
static doublecomplex c_b16 = {-1.,0.};

doublereal zqpt01_(integer *m, integer *n, integer *k, doublecomplex *a, 
	doublecomplex *af, integer *lda, doublecomplex *tau, integer *jpvt, 
	doublecomplex *work, integer *lwork)
{
    /* System generated locals */
    integer a_dim1, a_offset, af_dim1, af_offset, i__1, i__2, i__3, i__4;
    doublereal ret_val;

    /* Local variables */
    static integer i__, j, info;
    static doublereal norma, rwork[1];
    extern /* Subroutine */ int zcopy_(integer *, doublecomplex *, integer *, 
	    doublecomplex *, integer *), zaxpy_(integer *, doublecomplex *, 
	    doublecomplex *, integer *, doublecomplex *, integer *);
    extern doublereal dlamch_(char *);
    extern /* Subroutine */ int xerbla_(char *, integer *);
    extern doublereal zlange_(char *, integer *, integer *, doublecomplex *, 
	    integer *, doublereal *);
    extern /* Subroutine */ int zunmqr_(char *, char *, integer *, integer *, 
	    integer *, doublecomplex *, integer *, doublecomplex *, 
	    doublecomplex *, integer *, doublecomplex *, integer *, integer *);


/*  -- LAPACK test routine (version 3.1) --   
       Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..   
       November 2006   


    Purpose   
    =======   

    ZQPT01 tests the QR-factorization with pivoting of a matrix A.  The   
    array AF contains the (possibly partial) QR-factorization of A, where   
    the upper triangle of AF(1:k,1:k) is a partial triangular factor,   
    the entries below the diagonal in the first k columns are the   
    Householder vectors, and the rest of AF contains a partially updated   
    matrix.   

    This function returns ||A*P - Q*R||/(||norm(A)||*eps*M)   

    Arguments   
    =========   

    M       (input) INTEGER   
            The number of rows of the matrices A and AF.   

    N       (input) INTEGER   
            The number of columns of the matrices A and AF.   

    K       (input) INTEGER   
            The number of columns of AF that have been reduced   
            to upper triangular form.   

    A       (input) COMPLEX*16 array, dimension (LDA, N)   
            The original matrix A.   

    AF      (input) COMPLEX*16 array, dimension (LDA,N)   
            The (possibly partial) output of ZGEQPF.  The upper triangle   
            of AF(1:k,1:k) is a partial triangular factor, the entries   
            below the diagonal in the first k columns are the Householder   
            vectors, and the rest of AF contains a partially updated   
            matrix.   

    LDA     (input) INTEGER   
            The leading dimension of the arrays A and AF.   

    TAU     (input) COMPLEX*16 array, dimension (K)   
            Details of the Householder transformations as returned by   
            ZGEQPF.   

    JPVT    (input) INTEGER array, dimension (N)   
            Pivot information as returned by ZGEQPF.   

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

    LWORK   (input) INTEGER   
            The length of the array WORK.  LWORK >= M*N+N.   

    =====================================================================   


       Parameter adjustments */
    af_dim1 = *lda;
    af_offset = 1 + af_dim1;
    af -= af_offset;
    a_dim1 = *lda;
    a_offset = 1 + a_dim1;
    a -= a_offset;
    --tau;
    --jpvt;
    --work;

    /* Function Body */
    ret_val = 0.;

/*     Test if there is enough workspace */

    if (*lwork < *m * *n + *n) {
	xerbla_("ZQPT01", &c__10);
	return ret_val;
    }

/*     Quick return if possible */

    if (*m <= 0 || *n <= 0) {
	return ret_val;
    }

    norma = zlange_("One-norm", m, n, &a[a_offset], lda, rwork);

    i__1 = *k;
    for (j = 1; j <= i__1; ++j) {
	i__2 = min(j,*m);
	for (i__ = 1; i__ <= i__2; ++i__) {
	    i__3 = (j - 1) * *m + i__;
	    i__4 = i__ + j * af_dim1;
	    work[i__3].r = af[i__4].r, work[i__3].i = af[i__4].i;
/* L10: */
	}
	i__2 = *m;
	for (i__ = j + 1; i__ <= i__2; ++i__) {
	    i__3 = (j - 1) * *m + i__;
	    work[i__3].r = 0., work[i__3].i = 0.;
/* L20: */
	}
/* L30: */
    }
    i__1 = *n;
    for (j = *k + 1; j <= i__1; ++j) {
	zcopy_(m, &af[j * af_dim1 + 1], &c__1, &work[(j - 1) * *m + 1], &c__1)
		;
/* L40: */
    }

    i__1 = *lwork - *m * *n;
    zunmqr_("Left", "No transpose", m, n, k, &af[af_offset], lda, &tau[1], &
	    work[1], m, &work[*m * *n + 1], &i__1, &info);

    i__1 = *n;
    for (j = 1; j <= i__1; ++j) {

/*        Compare i-th column of QR and jpvt(i)-th column of A */

	zaxpy_(m, &c_b16, &a[jpvt[j] * a_dim1 + 1], &c__1, &work[(j - 1) * *m 
		+ 1], &c__1);
/* L50: */
    }

    ret_val = zlange_("One-norm", m, n, &work[1], m, rwork) / ((
	    doublereal) max(*m,*n) * dlamch_("Epsilon"));
    if (norma != 0.) {
	ret_val /= norma;
    }

    return ret_val;

/*     End of ZQPT01 */

} /* zqpt01_ */