text: /* cla_gbrcond_x.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"
  #include "blaswrap.h"
  
  /* Table of constant values */
  
  static integer c__1 = 1;
  
  doublereal cla_gbrcond_x__(char *trans, integer *n, integer *kl, integer *ku, 
  	complex *ab, integer *ldab, complex *afb, integer *ldafb, integer *
  	ipiv, complex *x, integer *info, complex *work, real *rwork, ftnlen 
  	trans_len)
  {
      /* System generated locals */
      integer ab_dim1, ab_offset, afb_dim1, afb_offset, i__1, i__2, i__3, i__4;
      real ret_val, r__1, r__2;
      complex q__1, q__2;
  
      /* Builtin functions */
      double r_imag(complex *);
      void c_div(complex *, complex *, complex *);
  
      /* Local variables */
      integer i__, j, kd, ke;
      real tmp;
      integer kase;
      extern logical lsame_(char *, char *);
      integer isave[3];
      real anorm;
      extern /* Subroutine */ int clacn2_(integer *, complex *, complex *, real 
  	    *, integer *, integer *), xerbla_(char *, integer *), 
  	    cgbtrs_(char *, integer *, integer *, integer *, integer *, 
  	    complex *, integer *, integer *, complex *, integer *, integer *);
      real ainvnm;
      logical notrans;
  
  
  /*     -- LAPACK routine (version 3.2.1)                               -- */
  /*     -- Contributed by James Demmel, Deaglan Halligan, Yozo Hida and -- */
  /*     -- Jason Riedy of Univ. of California Berkeley.                 -- */
  /*     -- April 2009                                                   -- */
  
  /*     -- LAPACK is a software package provided by Univ. of Tennessee, -- */
  /*     -- Univ. of California Berkeley and NAG Ltd.                    -- */
  
  /*     .. */
  /*     .. Scalar Arguments .. */
  /*     .. */
  /*     .. Array Arguments .. */
  /*     .. */
  
  /*  Purpose */
  /*  ======= */
  
  /*     CLA_GBRCOND_X Computes the infinity norm condition number of */
  /*     op(A) * diag(X) where X is a COMPLEX vector. */
  
  /*  Arguments */
  /*  ========= */
  
  /*     TRANS   (input) CHARACTER*1 */
  /*     Specifies the form of the system of equations: */
  /*       = 'N':  A * X = B     (No transpose) */
  /*       = 'T':  A**T * X = B  (Transpose) */
  /*       = 'C':  A**H * X = B  (Conjugate Transpose = Transpose) */
  
  /*     N       (input) INTEGER */
  /*     The number of linear equations, i.e., the order of the */
  /*     matrix A.  N >= 0. */
  
  /*     KL      (input) INTEGER */
  /*     The number of subdiagonals within the band of A.  KL >= 0. */
  
  /*     KU      (input) INTEGER */
  /*     The number of superdiagonals within the band of A.  KU >= 0. */
  
  /*     AB      (input) COMPLEX array, dimension (LDAB,N) */
  /*     On entry, the matrix A in band storage, in rows 1 to KL+KU+1. */
  /*     The j-th column of A is stored in the j-th column of the */
  /*     array AB as follows: */
  /*     AB(KU+1+i-j,j) = A(i,j) for max(1,j-KU)<=i<=min(N,j+kl) */
  
  /*     LDAB    (input) INTEGER */
  /*     The leading dimension of the array AB.  LDAB >= KL+KU+1. */
  
  /*     AFB     (input) COMPLEX array, dimension (LDAFB,N) */
  /*     Details of the LU factorization of the band matrix A, as */
  /*     computed by CGBTRF.  U is stored as an upper triangular */
  /*     band matrix with KL+KU superdiagonals in rows 1 to KL+KU+1, */
  /*     and the multipliers used during the factorization are stored */
  /*     in rows KL+KU+2 to 2*KL+KU+1. */
  
  /*     LDAFB   (input) INTEGER */
  /*     The leading dimension of the array AFB.  LDAFB >= 2*KL+KU+1. */
  
  /*     IPIV    (input) INTEGER array, dimension (N) */
  /*     The pivot indices from the factorization A = P*L*U */
  /*     as computed by CGBTRF; row i of the matrix was interchanged */
  /*     with row IPIV(i). */
  
  /*     X       (input) COMPLEX array, dimension (N) */
  /*     The vector X in the formula op(A) * diag(X). */
  
  /*     INFO    (output) INTEGER */
  /*       = 0:  Successful exit. */
  /*     i > 0:  The ith argument is invalid. */
  
  /*     WORK    (input) COMPLEX array, dimension (2*N). */
  /*     Workspace. */
  
  /*     RWORK   (input) REAL array, dimension (N). */
  /*     Workspace. */
  
  /*  ===================================================================== */
  
  /*     .. Local Scalars .. */
  /*     .. */
  /*     .. Local Arrays .. */
  /*     .. */
  /*     .. External Functions .. */
  /*     .. */
  /*     .. External Subroutines .. */
  /*     .. */
  /*     .. Intrinsic Functions .. */
  /*     .. */
  /*     .. Statement Functions .. */
  /*     .. */
  /*     .. Statement Function Definitions .. */
  /*     .. */
  /*     .. Executable Statements .. */
  
      /* Parameter adjustments */
      ab_dim1 = *ldab;
      ab_offset = 1 + ab_dim1;
      ab -= ab_offset;
      afb_dim1 = *ldafb;
      afb_offset = 1 + afb_dim1;
      afb -= afb_offset;
      --ipiv;
      --x;
      --work;
      --rwork;
  
      /* Function Body */
      ret_val = 0.f;
  
      *info = 0;
      notrans = lsame_(trans, "N");
      if (! notrans && ! lsame_(trans, "T") && ! lsame_(
  	    trans, "C")) {
  	*info = -1;
      } else if (*n < 0) {
  	*info = -2;
      } else if (*kl < 0 || *kl > *n - 1) {
  	*info = -3;
      } else if (*ku < 0 || *ku > *n - 1) {
  	*info = -4;
      } else if (*ldab < *kl + *ku + 1) {
  	*info = -6;
      } else if (*ldafb < (*kl << 1) + *ku + 1) {
  	*info = -8;
      }
      if (*info != 0) {
  	i__1 = -(*info);
  	xerbla_("CLA_GBRCOND_X", &i__1);
  	return ret_val;
      }
  
  /*     Compute norm of op(A)*op2(C). */
  
      kd = *ku + 1;
      ke = *kl + 1;
      anorm = 0.f;
      if (notrans) {
  	i__1 = *n;
  	for (i__ = 1; i__ <= i__1; ++i__) {
  	    tmp = 0.f;
  /* Computing MAX */
  	    i__2 = i__ - *kl;
  /* Computing MIN */
  	    i__4 = i__ + *ku;
  	    i__3 = min(i__4,*n);
  	    for (j = max(i__2,1); j <= i__3; ++j) {
  		i__2 = kd + i__ - j + j * ab_dim1;
  		i__4 = j;
  		q__2.r = ab[i__2].r * x[i__4].r - ab[i__2].i * x[i__4].i, 
  			q__2.i = ab[i__2].r * x[i__4].i + ab[i__2].i * x[i__4]
  			.r;
  		q__1.r = q__2.r, q__1.i = q__2.i;
  		tmp += (r__1 = q__1.r, dabs(r__1)) + (r__2 = r_imag(&q__1), 
  			dabs(r__2));
  	    }
  	    rwork[i__] = tmp;
  	    anorm = dmax(anorm,tmp);
  	}
      } else {
  	i__1 = *n;
  	for (i__ = 1; i__ <= i__1; ++i__) {
  	    tmp = 0.f;
  /* Computing MAX */
  	    i__3 = i__ - *kl;
  /* Computing MIN */
  	    i__4 = i__ + *ku;
  	    i__2 = min(i__4,*n);
  	    for (j = max(i__3,1); j <= i__2; ++j) {
  		i__3 = ke - i__ + j + i__ * ab_dim1;
  		i__4 = j;
  		q__2.r = ab[i__3].r * x[i__4].r - ab[i__3].i * x[i__4].i, 
  			q__2.i = ab[i__3].r * x[i__4].i + ab[i__3].i * x[i__4]
  			.r;
  		q__1.r = q__2.r, q__1.i = q__2.i;
  		tmp += (r__1 = q__1.r, dabs(r__1)) + (r__2 = r_imag(&q__1), 
  			dabs(r__2));
  	    }
  	    rwork[i__] = tmp;
  	    anorm = dmax(anorm,tmp);
  	}
      }
  
  /*     Quick return if possible. */
  
      if (*n == 0) {
  	ret_val = 1.f;
  	return ret_val;
      } else if (anorm == 0.f) {
  	return ret_val;
      }
  
  /*     Estimate the norm of inv(op(A)). */
  
      ainvnm = 0.f;
  
      kase = 0;
  L10:
      clacn2_(n, &work[*n + 1], &work[1], &ainvnm, &kase, isave);
      if (kase != 0) {
  	if (kase == 2) {
  
  /*           Multiply by R. */
  
  	    i__1 = *n;
  	    for (i__ = 1; i__ <= i__1; ++i__) {
  		i__2 = i__;
  		i__3 = i__;
  		i__4 = i__;
  		q__1.r = rwork[i__4] * work[i__3].r, q__1.i = rwork[i__4] * 
  			work[i__3].i;
  		work[i__2].r = q__1.r, work[i__2].i = q__1.i;
  	    }
  
  	    if (notrans) {
  		cgbtrs_("No transpose", n, kl, ku, &c__1, &afb[afb_offset], 
  			ldafb, &ipiv[1], &work[1], n, info);
  	    } else {
  		cgbtrs_("Conjugate transpose", n, kl, ku, &c__1, &afb[
  			afb_offset], ldafb, &ipiv[1], &work[1], n, info);
  	    }
  
  /*           Multiply by inv(X). */
  
  	    i__1 = *n;
  	    for (i__ = 1; i__ <= i__1; ++i__) {
  		i__2 = i__;
  		c_div(&q__1, &work[i__], &x[i__]);
  		work[i__2].r = q__1.r, work[i__2].i = q__1.i;
  	    }
  	} else {
  
  /*           Multiply by inv(X'). */
  
  	    i__1 = *n;
  	    for (i__ = 1; i__ <= i__1; ++i__) {
  		i__2 = i__;
  		c_div(&q__1, &work[i__], &x[i__]);
  		work[i__2].r = q__1.r, work[i__2].i = q__1.i;
  	    }
  
  	    if (notrans) {
  		cgbtrs_("Conjugate transpose", n, kl, ku, &c__1, &afb[
  			afb_offset], ldafb, &ipiv[1], &work[1], n, info);
  	    } else {
  		cgbtrs_("No transpose", n, kl, ku, &c__1, &afb[afb_offset], 
  			ldafb, &ipiv[1], &work[1], n, info);
  	    }
  
  /*           Multiply by R. */
  
  	    i__1 = *n;
  	    for (i__ = 1; i__ <= i__1; ++i__) {
  		i__2 = i__;
  		i__3 = i__;
  		i__4 = i__;
  		q__1.r = rwork[i__4] * work[i__3].r, q__1.i = rwork[i__4] * 
  			work[i__3].i;
  		work[i__2].r = q__1.r, work[i__2].i = q__1.i;
  	    }
  	}
  	goto L10;
      }
  
  /*     Compute the estimate of the reciprocal condition number. */
  
      if (ainvnm != 0.f) {
  	ret_val = 1.f / ainvnm;
      }
  
      return ret_val;
  
  } /* cla_gbrcond_x__ */
  