#include "blaswrap.h"
/* crzt01.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__8 = 8;
static complex c_b6 = {0.f,0.f};
static integer c__1 = 1;
static complex c_b15 = {-1.f,0.f};

doublereal crzt01_(integer *m, integer *n, complex *a, complex *af, integer *
	lda, complex *tau, complex *work, integer *lwork)
{
    /* System generated locals */
    integer a_dim1, a_offset, af_dim1, af_offset, i__1, i__2, i__3, i__4;
    real ret_val;

    /* Local variables */
    static integer i__, j, info;
    static real norma;
    extern /* Subroutine */ int caxpy_(integer *, complex *, complex *, 
	    integer *, complex *, integer *);
    static real rwork[1];
    extern doublereal clange_(char *, integer *, integer *, complex *, 
	    integer *, real *), slamch_(char *);
    extern /* Subroutine */ int claset_(char *, integer *, integer *, complex 
	    *, complex *, complex *, integer *), xerbla_(char *, 
	    integer *), cunmrz_(char *, char *, integer *, integer *, 
	    integer *, integer *, complex *, integer *, complex *, complex *, 
	    integer *, complex *, integer *, integer *);


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


    Purpose   
    =======   

    CRZT01 returns   
         || A - R*Q || / ( M * eps * ||A|| )   
    for an upper trapezoidal A that was factored with CTZRZF.   

    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.   

    A       (input) COMPLEX array, dimension (LDA,N)   
            The original upper trapezoidal M by N matrix A.   

    AF      (input) COMPLEX array, dimension (LDA,N)   
            The output of CTZRZF for input matrix A.   
            The lower triangle is not referenced.   

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

    TAU     (input) COMPLEX array, dimension (M)   
            Details of the  Householder transformations as returned by   
            CTZRZF.   

    WORK    (workspace) COMPLEX array, dimension (LWORK)   

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

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


       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;
    --work;

    /* Function Body */
    ret_val = 0.f;

    if (*lwork < *m * *n + *m) {
	xerbla_("CRZT01", &c__8);
	return ret_val;
    }

/*     Quick return if possible */

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

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

/*     Copy upper triangle R */

    claset_("Full", m, n, &c_b6, &c_b6, &work[1], m);
    i__1 = *m;
    for (j = 1; j <= i__1; ++j) {
	i__2 = j;
	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: */
	}
/* L20: */
    }

/*     R = R * P(1) * ... *P(m) */

    i__1 = *n - *m;
    i__2 = *lwork - *m * *n;
    cunmrz_("Right", "No tranpose", m, n, m, &i__1, &af[af_offset], lda, &tau[
	    1], &work[1], m, &work[*m * *n + 1], &i__2, &info);

/*     R = R - A */

    i__1 = *n;
    for (i__ = 1; i__ <= i__1; ++i__) {
	caxpy_(m, &c_b15, &a[i__ * a_dim1 + 1], &c__1, &work[(i__ - 1) * *m + 
		1], &c__1);
/* L30: */
    }

    ret_val = clange_("One-norm", m, n, &work[1], m, rwork);

    ret_val /= slamch_("Epsilon") * (real) max(*m,*n);
    if (norma != 0.f) {
	ret_val /= norma;
    }

    return ret_val;

/*     End of CRZT01 */

} /* crzt01_ */