#include "blaswrap.h"
/* ctzt02.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__7 = 7;
static complex c_b5 = {0.f,0.f};
static complex c_b6 = {1.f,0.f};

doublereal ctzt02_(integer *m, integer *n, complex *af, integer *lda, complex 
	*tau, complex *work, integer *lwork)
{
    /* System generated locals */
    integer af_dim1, af_offset, i__1, i__2, i__3;
    real ret_val;
    complex q__1;

    /* Builtin functions */
    void r_cnjg(complex *, complex *);

    /* Local variables */
    static integer i__;
    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 *), clatzm_(char *, integer *, integer *, complex 
	    *, integer *, complex *, complex *, complex *, integer *, complex 
	    *);


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


    Purpose   
    =======   

    CTZT02 returns   
         || I - Q'*Q || / ( M * eps)   
    where the matrix Q is defined by the Householder transformations   
    generated by CTZRQF.   

    Arguments   
    =========   

    M       (input) INTEGER   
            The number of rows of the matrix AF.   

    N       (input) INTEGER   
            The number of columns of the matrix AF.   

    AF      (input) COMPLEX array, dimension (LDA,N)   
            The output of CTZRQF.   

    LDA     (input) INTEGER   
            The leading dimension of the array AF.   

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

    WORK    (workspace) COMPLEX array, dimension (LWORK)   

    LWORK   (input) INTEGER   
            length of WORK array. Must be >= N*N+N   

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


       Parameter adjustments */
    af_dim1 = *lda;
    af_offset = 1 + af_dim1;
    af -= af_offset;
    --tau;
    --work;

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

    if (*lwork < *n * *n + *n) {
	xerbla_("CTZT02", &c__7);
	return ret_val;
    }

/*     Quick return if possible */

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

/*     Q := I */

    claset_("Full", n, n, &c_b5, &c_b6, &work[1], n);

/*     Q := P(1) * ... * P(m) * Q */

    for (i__ = *m; i__ >= 1; --i__) {
	i__1 = *n - *m + 1;
	clatzm_("Left", &i__1, n, &af[i__ + (*m + 1) * af_dim1], lda, &tau[
		i__], &work[i__], &work[*m + 1], n, &work[*n * *n + 1]);
/* L10: */
    }

/*     Q := P(m)' * ... * P(1)' * Q */

    i__1 = *m;
    for (i__ = 1; i__ <= i__1; ++i__) {
	i__2 = *n - *m + 1;
	r_cnjg(&q__1, &tau[i__]);
	clatzm_("Left", &i__2, n, &af[i__ + (*m + 1) * af_dim1], lda, &q__1, &
		work[i__], &work[*m + 1], n, &work[*n * *n + 1]);
/* L20: */
    }

/*     Q := Q - I */

    i__1 = *n;
    for (i__ = 1; i__ <= i__1; ++i__) {
	i__2 = (i__ - 1) * *n + i__;
	i__3 = (i__ - 1) * *n + i__;
	q__1.r = work[i__3].r - 1.f, q__1.i = work[i__3].i;
	work[i__2].r = q__1.r, work[i__2].i = q__1.i;
/* L30: */
    }

    ret_val = clange_("One-norm", n, n, &work[1], n, rwork) / (
	    slamch_("Epsilon") * (real) max(*m,*n));
    return ret_val;

/*     End of CTZT02 */

} /* ctzt02_ */