/*  -- translated by f2c (version 20100827).
   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__1 = 1;
static doublereal c_b18 = .001;

/* Subroutine */ int igraphdstemr_(char *jobz, char *range, integer *n, doublereal *
	d__, doublereal *e, doublereal *vl, doublereal *vu, integer *il, 
	integer *iu, integer *m, doublereal *w, doublereal *z__, integer *ldz,
	 integer *nzc, integer *isuppz, logical *tryrac, doublereal *work, 
	integer *lwork, integer *iwork, integer *liwork, integer *info)
{
    /* System generated locals */
    integer z_dim1, z_offset, i__1, i__2;
    doublereal d__1, d__2;

    /* Builtin functions */
    double sqrt(doublereal);

    /* Local variables */
    integer i__, j;
    doublereal r1, r2;
    integer jj;
    doublereal cs;
    integer in;
    doublereal sn, wl, wu;
    integer iil, iiu;
    doublereal eps, tmp;
    integer indd, iend, jblk, wend;
    doublereal rmin, rmax;
    integer itmp;
    doublereal tnrm;
    extern /* Subroutine */ int igraphdlae2_(doublereal *, doublereal *, doublereal 
	    *, doublereal *, doublereal *);
    integer inde2, itmp2;
    doublereal rtol1, rtol2;
    extern /* Subroutine */ int igraphdscal_(integer *, doublereal *, doublereal *, 
	    integer *);
    doublereal scale;
    integer indgp;
    extern logical igraphlsame_(char *, char *);
    integer iinfo, iindw, ilast;
    extern /* Subroutine */ int igraphdcopy_(integer *, doublereal *, integer *, 
	    doublereal *, integer *), igraphdswap_(integer *, doublereal *, integer 
	    *, doublereal *, integer *);
    integer lwmin;
    logical wantz;
    extern /* Subroutine */ int igraphdlaev2_(doublereal *, doublereal *, 
	    doublereal *, doublereal *, doublereal *, doublereal *, 
	    doublereal *);
    extern doublereal igraphdlamch_(char *);
    logical alleig;
    integer ibegin;
    logical indeig;
    integer iindbl;
    logical valeig;
    extern /* Subroutine */ int igraphdlarrc_(char *, integer *, doublereal *, 
	    doublereal *, doublereal *, doublereal *, doublereal *, integer *,
	     integer *, integer *, integer *), igraphdlarre_(char *, 
	    integer *, doublereal *, doublereal *, integer *, integer *, 
	    doublereal *, doublereal *, doublereal *, doublereal *, 
	    doublereal *, doublereal *, integer *, integer *, integer *, 
	    doublereal *, doublereal *, doublereal *, integer *, integer *, 
	    doublereal *, doublereal *, doublereal *, integer *, integer *);
    integer wbegin;
    doublereal safmin;
    extern /* Subroutine */ int igraphdlarrj_(integer *, doublereal *, doublereal *,
	     integer *, integer *, doublereal *, integer *, doublereal *, 
	    doublereal *, doublereal *, integer *, doublereal *, doublereal *,
	     integer *), igraphxerbla_(char *, integer *, ftnlen);
    doublereal bignum;
    integer inderr, iindwk, indgrs, offset;
    extern doublereal igraphdlanst_(char *, integer *, doublereal *, doublereal *);
    extern /* Subroutine */ int igraphdlarrr_(integer *, doublereal *, doublereal *,
	     integer *), igraphdlarrv_(integer *, doublereal *, doublereal *, 
	    doublereal *, doublereal *, doublereal *, integer *, integer *, 
	    integer *, integer *, doublereal *, doublereal *, doublereal *, 
	    doublereal *, doublereal *, doublereal *, integer *, integer *, 
	    doublereal *, doublereal *, integer *, integer *, doublereal *, 
	    integer *, integer *), igraphdlasrt_(char *, integer *, doublereal *, 
	    integer *);
    doublereal thresh;
    integer iinspl, ifirst, indwrk, liwmin, nzcmin;
    doublereal pivmin;
    integer nsplit;
    doublereal smlnum;
    logical lquery, zquery;


/*  -- LAPACK computational routine (version 3.2.2)                                  --   
    -- LAPACK is a software package provided by Univ. of Tennessee,    --   
    -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--   
    -- June 2010                                                       --   


    Purpose   
    =======   

    DSTEMR computes selected eigenvalues and, optionally, eigenvectors   
    of a real symmetric tridiagonal matrix T. Any such unreduced matrix has   
    a well defined set of pairwise different real eigenvalues, the corresponding   
    real eigenvectors are pairwise orthogonal.   

    The spectrum may be computed either completely or partially by specifying   
    either an interval (VL,VU] or a range of indices IL:IU for the desired   
    eigenvalues.   

    Depending on the number of desired eigenvalues, these are computed either   
    by bisection or the dqds algorithm. Numerically orthogonal eigenvectors are   
    computed by the use of various suitable L D L^T factorizations near clusters   
    of close eigenvalues (referred to as RRRs, Relatively Robust   
    Representations). An informal sketch of the algorithm follows.   

    For each unreduced block (submatrix) of T,   
       (a) Compute T - sigma I  = L D L^T, so that L and D   
           define all the wanted eigenvalues to high relative accuracy.   
           This means that small relative changes in the entries of D and L   
           cause only small relative changes in the eigenvalues and   
           eigenvectors. The standard (unfactored) representation of the   
           tridiagonal matrix T does not have this property in general.   
       (b) Compute the eigenvalues to suitable accuracy.   
           If the eigenvectors are desired, the algorithm attains full   
           accuracy of the computed eigenvalues only right before   
           the corresponding vectors have to be computed, see steps c) and d).   
       (c) For each cluster of close eigenvalues, select a new   
           shift close to the cluster, find a new factorization, and refine   
           the shifted eigenvalues to suitable accuracy.   
       (d) For each eigenvalue with a large enough relative separation compute   
           the corresponding eigenvector by forming a rank revealing twisted   
           factorization. Go back to (c) for any clusters that remain.   

    For more details, see:   
    - Inderjit S. Dhillon and Beresford N. Parlett: "Multiple representations   
      to compute orthogonal eigenvectors of symmetric tridiagonal matrices,"   
      Linear Algebra and its Applications, 387(1), pp. 1-28, August 2004.   
    - Inderjit Dhillon and Beresford Parlett: "Orthogonal Eigenvectors and   
      Relative Gaps," SIAM Journal on Matrix Analysis and Applications, Vol. 25,   
      2004.  Also LAPACK Working Note 154.   
    - Inderjit Dhillon: "A new O(n^2) algorithm for the symmetric   
      tridiagonal eigenvalue/eigenvector problem",   
      Computer Science Division Technical Report No. UCB/CSD-97-971,   
      UC Berkeley, May 1997.   

    Further Details   
    1.DSTEMR works only on machines which follow IEEE-754   
    floating-point standard in their handling of infinities and NaNs.   
    This permits the use of efficient inner loops avoiding a check for   
    zero divisors.   

    Arguments   
    =========   

    JOBZ    (input) CHARACTER*1   
            = 'N':  Compute eigenvalues only;   
            = 'V':  Compute eigenvalues and eigenvectors.   

    RANGE   (input) CHARACTER*1   
            = 'A': all eigenvalues will be found.   
            = 'V': all eigenvalues in the half-open interval (VL,VU]   
                   will be found.   
            = 'I': the IL-th through IU-th eigenvalues will be found.   

    N       (input) INTEGER   
            The order of the matrix.  N >= 0.   

    D       (input/output) DOUBLE PRECISION array, dimension (N)   
            On entry, the N diagonal elements of the tridiagonal matrix   
            T. On exit, D is overwritten.   

    E       (input/output) DOUBLE PRECISION array, dimension (N)   
            On entry, the (N-1) subdiagonal elements of the tridiagonal   
            matrix T in elements 1 to N-1 of E. E(N) need not be set on   
            input, but is used internally as workspace.   
            On exit, E is overwritten.   

    VL      (input) DOUBLE PRECISION   
    VU      (input) DOUBLE PRECISION   
            If RANGE='V', the lower and upper bounds of the interval to   
            be searched for eigenvalues. VL < VU.   
            Not referenced if RANGE = 'A' or 'I'.   

    IL      (input) INTEGER   
    IU      (input) INTEGER   
            If RANGE='I', the indices (in ascending order) of the   
            smallest and largest eigenvalues to be returned.   
            1 <= IL <= IU <= N, if N > 0.   
            Not referenced if RANGE = 'A' or 'V'.   

    M       (output) INTEGER   
            The total number of eigenvalues found.  0 <= M <= N.   
            If RANGE = 'A', M = N, and if RANGE = 'I', M = IU-IL+1.   

    W       (output) DOUBLE PRECISION array, dimension (N)   
            The first M elements contain the selected eigenvalues in   
            ascending order.   

    Z       (output) DOUBLE PRECISION array, dimension (LDZ, max(1,M) )   
            If JOBZ = 'V', and if INFO = 0, then the first M columns of Z   
            contain the orthonormal eigenvectors of the matrix T   
            corresponding to the selected eigenvalues, with the i-th   
            column of Z holding the eigenvector associated with W(i).   
            If JOBZ = 'N', then Z is not referenced.   
            Note: the user must ensure that at least max(1,M) columns are   
            supplied in the array Z; if RANGE = 'V', the exact value of M   
            is not known in advance and can be computed with a workspace   
            query by setting NZC = -1, see below.   

    LDZ     (input) INTEGER   
            The leading dimension of the array Z.  LDZ >= 1, and if   
            JOBZ = 'V', then LDZ >= max(1,N).   

    NZC     (input) INTEGER   
            The number of eigenvectors to be held in the array Z.   
            If RANGE = 'A', then NZC >= max(1,N).   
            If RANGE = 'V', then NZC >= the number of eigenvalues in (VL,VU].   
            If RANGE = 'I', then NZC >= IU-IL+1.   
            If NZC = -1, then a workspace query is assumed; the   
            routine calculates the number of columns of the array Z that   
            are needed to hold the eigenvectors.   
            This value is returned as the first entry of the Z array, and   
            no error message related to NZC is issued by XERBLA.   

    ISUPPZ  (output) INTEGER ARRAY, dimension ( 2*max(1,M) )   
            The support of the eigenvectors in Z, i.e., the indices   
            indicating the nonzero elements in Z. The i-th computed eigenvector   
            is nonzero only in elements ISUPPZ( 2*i-1 ) through   
            ISUPPZ( 2*i ). This is relevant in the case when the matrix   
            is split. ISUPPZ is only accessed when JOBZ is 'V' and N > 0.   

    TRYRAC  (input/output) LOGICAL   
            If TRYRAC.EQ..TRUE., indicates that the code should check whether   
            the tridiagonal matrix defines its eigenvalues to high relative   
            accuracy.  If so, the code uses relative-accuracy preserving   
            algorithms that might be (a bit) slower depending on the matrix.   
            If the matrix does not define its eigenvalues to high relative   
            accuracy, the code can uses possibly faster algorithms.   
            If TRYRAC.EQ..FALSE., the code is not required to guarantee   
            relatively accurate eigenvalues and can use the fastest possible   
            techniques.   
            On exit, a .TRUE. TRYRAC will be set to .FALSE. if the matrix   
            does not define its eigenvalues to high relative accuracy.   

    WORK    (workspace/output) DOUBLE PRECISION array, dimension (LWORK)   
            On exit, if INFO = 0, WORK(1) returns the optimal   
            (and minimal) LWORK.   

    LWORK   (input) INTEGER   
            The dimension of the array WORK. LWORK >= max(1,18*N)   
            if JOBZ = 'V', and LWORK >= max(1,12*N) if JOBZ = 'N'.   
            If LWORK = -1, then a workspace query is assumed; the routine   
            only calculates the optimal size of the WORK array, returns   
            this value as the first entry of the WORK array, and no error   
            message related to LWORK is issued by XERBLA.   

    IWORK   (workspace/output) INTEGER array, dimension (LIWORK)   
            On exit, if INFO = 0, IWORK(1) returns the optimal LIWORK.   

    LIWORK  (input) INTEGER   
            The dimension of the array IWORK.  LIWORK >= max(1,10*N)   
            if the eigenvectors are desired, and LIWORK >= max(1,8*N)   
            if only the eigenvalues are to be computed.   
            If LIWORK = -1, then a workspace query is assumed; the   
            routine only calculates the optimal size of the IWORK array,   
            returns this value as the first entry of the IWORK array, and   
            no error message related to LIWORK is issued by XERBLA.   

    INFO    (output) INTEGER   
            On exit, INFO   
            = 0:  successful exit   
            < 0:  if INFO = -i, the i-th argument had an illegal value   
            > 0:  if INFO = 1X, internal error in DLARRE,   
                  if INFO = 2X, internal error in DLARRV.   
                  Here, the digit X = ABS( IINFO ) < 10, where IINFO is   
                  the nonzero error code returned by DLARRE or   
                  DLARRV, respectively.   


    Further Details   
    ===============   

    Based on contributions by   
       Beresford Parlett, University of California, Berkeley, USA   
       Jim Demmel, University of California, Berkeley, USA   
       Inderjit Dhillon, University of Texas, Austin, USA   
       Osni Marques, LBNL/NERSC, USA   
       Christof Voemel, University of California, Berkeley, USA   

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


       Test the input parameters.   

       Parameter adjustments */
    --d__;
    --e;
    --w;
    z_dim1 = *ldz;
    z_offset = 1 + z_dim1;
    z__ -= z_offset;
    --isuppz;
    --work;
    --iwork;

    /* Function Body */
    wantz = igraphlsame_(jobz, "V");
    alleig = igraphlsame_(range, "A");
    valeig = igraphlsame_(range, "V");
    indeig = igraphlsame_(range, "I");

    lquery = *lwork == -1 || *liwork == -1;
    zquery = *nzc == -1;
/*     DSTEMR needs WORK of size 6*N, IWORK of size 3*N.   
       In addition, DLARRE needs WORK of size 6*N, IWORK of size 5*N.   
       Furthermore, DLARRV needs WORK of size 12*N, IWORK of size 7*N. */
    if (wantz) {
	lwmin = *n * 18;
	liwmin = *n * 10;
    } else {
/*        need less workspace if only the eigenvalues are wanted */
	lwmin = *n * 12;
	liwmin = *n << 3;
    }
    wl = 0.;
    wu = 0.;
    iil = 0;
    iiu = 0;
    if (valeig) {
/*        We do not reference VL, VU in the cases RANGE = 'I','A'   
          The interval (WL, WU] contains all the wanted eigenvalues.   
          It is either given by the user or computed in DLARRE. */
	wl = *vl;
	wu = *vu;
    } else if (indeig) {
/*        We do not reference IL, IU in the cases RANGE = 'V','A' */
	iil = *il;
	iiu = *iu;
    }

    *info = 0;
    if (! (wantz || igraphlsame_(jobz, "N"))) {
	*info = -1;
    } else if (! (alleig || valeig || indeig)) {
	*info = -2;
    } else if (*n < 0) {
	*info = -3;
    } else if (valeig && *n > 0 && wu <= wl) {
	*info = -7;
    } else if (indeig && (iil < 1 || iil > *n)) {
	*info = -8;
    } else if (indeig && (iiu < iil || iiu > *n)) {
	*info = -9;
    } else if (*ldz < 1 || wantz && *ldz < *n) {
	*info = -13;
    } else if (*lwork < lwmin && ! lquery) {
	*info = -17;
    } else if (*liwork < liwmin && ! lquery) {
	*info = -19;
    }

/*     Get machine constants. */

    safmin = igraphdlamch_("Safe minimum");
    eps = igraphdlamch_("Precision");
    smlnum = safmin / eps;
    bignum = 1. / smlnum;
    rmin = sqrt(smlnum);
/* Computing MIN */
    d__1 = sqrt(bignum), d__2 = 1. / sqrt(sqrt(safmin));
    rmax = min(d__1,d__2);

    if (*info == 0) {
	work[1] = (doublereal) lwmin;
	iwork[1] = liwmin;

	if (wantz && alleig) {
	    nzcmin = *n;
	} else if (wantz && valeig) {
	    igraphdlarrc_("T", n, vl, vu, &d__[1], &e[1], &safmin, &nzcmin, &itmp, &
		    itmp2, info);
	} else if (wantz && indeig) {
	    nzcmin = iiu - iil + 1;
	} else {
/*           WANTZ .EQ. FALSE. */
	    nzcmin = 0;
	}
	if (zquery && *info == 0) {
	    z__[z_dim1 + 1] = (doublereal) nzcmin;
	} else if (*nzc < nzcmin && ! zquery) {
	    *info = -14;
	}
    }
    if (*info != 0) {

	i__1 = -(*info);
	igraphxerbla_("DSTEMR", &i__1, (ftnlen)6);

	return 0;
    } else if (lquery || zquery) {
	return 0;
    }

/*     Handle N = 0, 1, and 2 cases immediately */

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

    if (*n == 1) {
	if (alleig || indeig) {
	    *m = 1;
	    w[1] = d__[1];
	} else {
	    if (wl < d__[1] && wu >= d__[1]) {
		*m = 1;
		w[1] = d__[1];
	    }
	}
	if (wantz && ! zquery) {
	    z__[z_dim1 + 1] = 1.;
	    isuppz[1] = 1;
	    isuppz[2] = 1;
	}
	return 0;
    }

    if (*n == 2) {
	if (! wantz) {
	    igraphdlae2_(&d__[1], &e[1], &d__[2], &r1, &r2);
	} else if (wantz && ! zquery) {
	    igraphdlaev2_(&d__[1], &e[1], &d__[2], &r1, &r2, &cs, &sn);
	}
	if (alleig || valeig && r2 > wl && r2 <= wu || indeig && iil == 1) {
	    ++(*m);
	    w[*m] = r2;
	    if (wantz && ! zquery) {
		z__[*m * z_dim1 + 1] = -sn;
		z__[*m * z_dim1 + 2] = cs;
/*              Note: At most one of SN and CS can be zero. */
		if (sn != 0.) {
		    if (cs != 0.) {
			isuppz[(*m << 1) - 1] = 1;
			isuppz[*m * 2] = 2;
		    } else {
			isuppz[(*m << 1) - 1] = 1;
			isuppz[*m * 2] = 1;
		    }
		} else {
		    isuppz[(*m << 1) - 1] = 2;
		    isuppz[*m * 2] = 2;
		}
	    }
	}
	if (alleig || valeig && r1 > wl && r1 <= wu || indeig && iiu == 2) {
	    ++(*m);
	    w[*m] = r1;
	    if (wantz && ! zquery) {
		z__[*m * z_dim1 + 1] = cs;
		z__[*m * z_dim1 + 2] = sn;
/*              Note: At most one of SN and CS can be zero. */
		if (sn != 0.) {
		    if (cs != 0.) {
			isuppz[(*m << 1) - 1] = 1;
			isuppz[*m * 2] = 2;
		    } else {
			isuppz[(*m << 1) - 1] = 1;
			isuppz[*m * 2] = 1;
		    }
		} else {
		    isuppz[(*m << 1) - 1] = 2;
		    isuppz[*m * 2] = 2;
		}
	    }
	}
	return 0;
    }
/*     Continue with general N */
    indgrs = 1;
    inderr = (*n << 1) + 1;
    indgp = *n * 3 + 1;
    indd = (*n << 2) + 1;
    inde2 = *n * 5 + 1;
    indwrk = *n * 6 + 1;

    iinspl = 1;
    iindbl = *n + 1;
    iindw = (*n << 1) + 1;
    iindwk = *n * 3 + 1;

/*     Scale matrix to allowable range, if necessary.   
       The allowable range is related to the PIVMIN parameter; see the   
       comments in DLARRD.  The preference for scaling small values   
       up is heuristic; we expect users' matrices not to be close to the   
       RMAX threshold. */

    scale = 1.;
    tnrm = igraphdlanst_("M", n, &d__[1], &e[1]);
    if (tnrm > 0. && tnrm < rmin) {
	scale = rmin / tnrm;
    } else if (tnrm > rmax) {
	scale = rmax / tnrm;
    }
    if (scale != 1.) {
	igraphdscal_(n, &scale, &d__[1], &c__1);
	i__1 = *n - 1;
	igraphdscal_(&i__1, &scale, &e[1], &c__1);
	tnrm *= scale;
	if (valeig) {
/*           If eigenvalues in interval have to be found,   
             scale (WL, WU] accordingly */
	    wl *= scale;
	    wu *= scale;
	}
    }

/*     Compute the desired eigenvalues of the tridiagonal after splitting   
       into smaller subblocks if the corresponding off-diagonal elements   
       are small   
       THRESH is the splitting parameter for DLARRE   
       A negative THRESH forces the old splitting criterion based on the   
       size of the off-diagonal. A positive THRESH switches to splitting   
       which preserves relative accuracy. */

    if (*tryrac) {
/*        Test whether the matrix warrants the more expensive relative approach. */
	igraphdlarrr_(n, &d__[1], &e[1], &iinfo);
    } else {
/*        The user does not care about relative accurately eigenvalues */
	iinfo = -1;
    }
/*     Set the splitting criterion */
    if (iinfo == 0) {
	thresh = eps;
    } else {
	thresh = -eps;
/*        relative accuracy is desired but T does not guarantee it */
	*tryrac = FALSE_;
    }

    if (*tryrac) {
/*        Copy original diagonal, needed to guarantee relative accuracy */
	igraphdcopy_(n, &d__[1], &c__1, &work[indd], &c__1);
    }
/*     Store the squares of the offdiagonal values of T */
    i__1 = *n - 1;
    for (j = 1; j <= i__1; ++j) {
/* Computing 2nd power */
	d__1 = e[j];
	work[inde2 + j - 1] = d__1 * d__1;
/* L5: */
    }
/*     Set the tolerance parameters for bisection */
    if (! wantz) {
/*        DLARRE computes the eigenvalues to full precision. */
	rtol1 = eps * 4.;
	rtol2 = eps * 4.;
    } else {
/*        DLARRE computes the eigenvalues to less than full precision.   
          DLARRV will refine the eigenvalue approximations, and we can   
          need less accurate initial bisection in DLARRE.   
          Note: these settings do only affect the subset case and DLARRE */
	rtol1 = sqrt(eps);
/* Computing MAX */
	d__1 = sqrt(eps) * .005, d__2 = eps * 4.;
	rtol2 = max(d__1,d__2);
    }
    igraphdlarre_(range, n, &wl, &wu, &iil, &iiu, &d__[1], &e[1], &work[inde2], &
	    rtol1, &rtol2, &thresh, &nsplit, &iwork[iinspl], m, &w[1], &work[
	    inderr], &work[indgp], &iwork[iindbl], &iwork[iindw], &work[
	    indgrs], &pivmin, &work[indwrk], &iwork[iindwk], &iinfo);
    if (iinfo != 0) {
	*info = abs(iinfo) + 10;
	return 0;
    }
/*     Note that if RANGE .NE. 'V', DLARRE computes bounds on the desired   
       part of the spectrum. All desired eigenvalues are contained in   
       (WL,WU] */
    if (wantz) {

/*        Compute the desired eigenvectors corresponding to the computed   
          eigenvalues */

	igraphdlarrv_(n, &wl, &wu, &d__[1], &e[1], &pivmin, &iwork[iinspl], m, &
		c__1, m, &c_b18, &rtol1, &rtol2, &w[1], &work[inderr], &work[
		indgp], &iwork[iindbl], &iwork[iindw], &work[indgrs], &z__[
		z_offset], ldz, &isuppz[1], &work[indwrk], &iwork[iindwk], &
		iinfo);
	if (iinfo != 0) {
	    *info = abs(iinfo) + 20;
	    return 0;
	}
    } else {
/*        DLARRE computes eigenvalues of the (shifted) root representation   
          DLARRV returns the eigenvalues of the unshifted matrix.   
          However, if the eigenvectors are not desired by the user, we need   
          to apply the corresponding shifts from DLARRE to obtain the   
          eigenvalues of the original matrix. */
	i__1 = *m;
	for (j = 1; j <= i__1; ++j) {
	    itmp = iwork[iindbl + j - 1];
	    w[j] += e[iwork[iinspl + itmp - 1]];
/* L20: */
	}
    }

    if (*tryrac) {
/*        Refine computed eigenvalues so that they are relatively accurate   
          with respect to the original matrix T. */
	ibegin = 1;
	wbegin = 1;
	i__1 = iwork[iindbl + *m - 1];
	for (jblk = 1; jblk <= i__1; ++jblk) {
	    iend = iwork[iinspl + jblk - 1];
	    in = iend - ibegin + 1;
	    wend = wbegin - 1;
/*           check if any eigenvalues have to be refined in this block */
L36:
	    if (wend < *m) {
		if (iwork[iindbl + wend] == jblk) {
		    ++wend;
		    goto L36;
		}
	    }
	    if (wend < wbegin) {
		ibegin = iend + 1;
		goto L39;
	    }
	    offset = iwork[iindw + wbegin - 1] - 1;
	    ifirst = iwork[iindw + wbegin - 1];
	    ilast = iwork[iindw + wend - 1];
	    rtol2 = eps * 4.;
	    igraphdlarrj_(&in, &work[indd + ibegin - 1], &work[inde2 + ibegin - 1], 
		    &ifirst, &ilast, &rtol2, &offset, &w[wbegin], &work[
		    inderr + wbegin - 1], &work[indwrk], &iwork[iindwk], &
		    pivmin, &tnrm, &iinfo);
	    ibegin = iend + 1;
	    wbegin = wend + 1;
L39:
	    ;
	}
    }

/*     If matrix was scaled, then rescale eigenvalues appropriately. */

    if (scale != 1.) {
	d__1 = 1. / scale;
	igraphdscal_(m, &d__1, &w[1], &c__1);
    }

/*     If eigenvalues are not in increasing order, then sort them,   
       possibly along with eigenvectors. */

    if (nsplit > 1) {
	if (! wantz) {
	    igraphdlasrt_("I", m, &w[1], &iinfo);
	    if (iinfo != 0) {
		*info = 3;
		return 0;
	    }
	} else {
	    i__1 = *m - 1;
	    for (j = 1; j <= i__1; ++j) {
		i__ = 0;
		tmp = w[j];
		i__2 = *m;
		for (jj = j + 1; jj <= i__2; ++jj) {
		    if (w[jj] < tmp) {
			i__ = jj;
			tmp = w[jj];
		    }
/* L50: */
		}
		if (i__ != 0) {
		    w[i__] = w[j];
		    w[j] = tmp;
		    if (wantz) {
			igraphdswap_(n, &z__[i__ * z_dim1 + 1], &c__1, &z__[j * 
				z_dim1 + 1], &c__1);
			itmp = isuppz[(i__ << 1) - 1];
			isuppz[(i__ << 1) - 1] = isuppz[(j << 1) - 1];
			isuppz[(j << 1) - 1] = itmp;
			itmp = isuppz[i__ * 2];
			isuppz[i__ * 2] = isuppz[j * 2];
			isuppz[j * 2] = itmp;
		    }
		}
/* L60: */
	    }
	}
    }


    work[1] = (doublereal) lwmin;
    iwork[1] = liwmin;
    return 0;

/*     End of DSTEMR */

} /* igraphdstemr_ */

