#include <cmath>
#include "../gmx_lapack.h"

void
F77_FUNC(dlaebz,DLAEBZ)(int *ijob,
	int *nitmax,
	int *n, 
	int *mmax,
	int *minp,
	int *nbmin,
	double *abstol, 
	double *reltol, 
	double *pivmin, 
	double *d__,
	double *e,
	double *e2, 
	int *nval,
	double *ab, 
	double *c__, 
	int *mout, 
	int *nab,
	double *work,
	int *iwork, 
	int *info)
{
    int nab_dim1, nab_offset, ab_dim1, ab_offset, i__1, i__2, i__3, i__4, 
	    i__5, i__6;
    double d__1, d__2, d__3, d__4;

    int j, kf, ji, kl, jp, jit;
    double tmp1, tmp2;
    int itmp1, itmp2, kfnew, klnew;

    nab_dim1 = *mmax;
    nab_offset = 1 + nab_dim1;
    nab -= nab_offset;
    ab_dim1 = *mmax;
    ab_offset = 1 + ab_dim1;
    ab -= ab_offset;
    --d__;
    --e;
    --e2;
    --nval;
    --c__;
    --work;
    --iwork;

    *info = 0;
    if (*ijob < 1 || *ijob > 3) {
	*info = -1;
	return;
    }

    if (*ijob == 1) {

	*mout = 0;

	i__1 = *minp;
	for (ji = 1; ji <= i__1; ++ji) {
	    for (jp = 1; jp <= 2; ++jp) {
		tmp1 = d__[1] - ab[ji + jp * ab_dim1];
		if (std::abs(tmp1) < *pivmin) {
		    tmp1 = -(*pivmin);
		}
		nab[ji + jp * nab_dim1] = 0;
		if (tmp1 <= 0.) {
		    nab[ji + jp * nab_dim1] = 1;
		}

		i__2 = *n;
		for (j = 2; j <= i__2; ++j) {
		    tmp1 = d__[j] - e2[j - 1] / tmp1 - ab[ji + jp * ab_dim1];
		    if (std::abs(tmp1) < *pivmin) {
			tmp1 = -(*pivmin);
		    }
		    if (tmp1 <= 0.) {
			++nab[ji + jp * nab_dim1];
		    }
		}
	    }
	    *mout = *mout + nab[ji + (nab_dim1 << 1)] - nab[ji + nab_dim1];
	}
	return;
    }

    kf = 1;
    kl = *minp;

    if (*ijob == 2) {
	i__1 = *minp;
	for (ji = 1; ji <= i__1; ++ji) {
	    c__[ji] = (ab[ji + ab_dim1] + ab[ji + (ab_dim1 << 1)]) * .5;
	}
    }

    i__1 = *nitmax;
    for (jit = 1; jit <= i__1; ++jit) {

	if (kl - kf + 1 >= *nbmin && *nbmin > 0) {

	    i__2 = kl;
	    for (ji = kf; ji <= i__2; ++ji) {

		work[ji] = d__[1] - c__[ji];
		iwork[ji] = 0;
		if (work[ji] <= *pivmin) {
		    iwork[ji] = 1;
		    d__1 = work[ji], d__2 = -(*pivmin);
		    work[ji] = (d__1<d__2) ? d__1 : d__2;
		}

		i__3 = *n;
		for (j = 2; j <= i__3; ++j) {
		    work[ji] = d__[j] - e2[j - 1] / work[ji] - c__[ji];
		    if (work[ji] <= *pivmin) {
			++iwork[ji];
			d__1 = work[ji], d__2 = -(*pivmin);
			work[ji] = (d__1<d__2) ? d__1 : d__2;
		    }
		}
	    }

	    if (*ijob <= 2) {

		klnew = kl;
		i__2 = kl;
		for (ji = kf; ji <= i__2; ++ji) {

		  i__5 = nab[ji + nab_dim1];
		  i__6 = iwork[ji];
		  i__3 = nab[ji + (nab_dim1 << 1)];
		  i__4 = (i__5>i__6) ? i__5 : i__6;
		    iwork[ji] = (i__3<i__4) ? i__3 : i__4;

		    if (iwork[ji] == nab[ji + (nab_dim1 << 1)]) {

			ab[ji + (ab_dim1 << 1)] = c__[ji];

		    } else if (iwork[ji] == nab[ji + nab_dim1]) {

			ab[ji + ab_dim1] = c__[ji];
		    } else {
			++klnew;
			if (klnew <= *mmax) {

			    ab[klnew + (ab_dim1 << 1)] = ab[ji + (ab_dim1 << 
				    1)];
			    nab[klnew + (nab_dim1 << 1)] = nab[ji + (nab_dim1 
				    << 1)];
			    ab[klnew + ab_dim1] = c__[ji];
			    nab[klnew + nab_dim1] = iwork[ji];
			    ab[ji + (ab_dim1 << 1)] = c__[ji];
			    nab[ji + (nab_dim1 << 1)] = iwork[ji];
			} else {
			    *info = *mmax + 1;
			}
		    }
		}
		if (*info != 0) {
		    return;
		}
		kl = klnew;
	    } else {

		i__2 = kl;
		for (ji = kf; ji <= i__2; ++ji) {
		    if (iwork[ji] <= nval[ji]) {
			ab[ji + ab_dim1] = c__[ji];
			nab[ji + nab_dim1] = iwork[ji];
		    }
		    if (iwork[ji] >= nval[ji]) {
			ab[ji + (ab_dim1 << 1)] = c__[ji];
			nab[ji + (nab_dim1 << 1)] = iwork[ji];
		    }
		}
	    }

	} else {

	    klnew = kl;
	    i__2 = kl;
	    for (ji = kf; ji <= i__2; ++ji) {

		tmp1 = c__[ji];
		tmp2 = d__[1] - tmp1;
		itmp1 = 0;
		if (tmp2 <= *pivmin) {
		    itmp1 = 1;
		    d__1 = tmp2, d__2 = -(*pivmin);
		    tmp2 = (d__1<d__2) ? d__1 : d__2;
		}

		i__3 = *n;
		for (j = 2; j <= i__3; ++j) {
		    tmp2 = d__[j] - e2[j - 1] / tmp2 - tmp1;
		    if (tmp2 <= *pivmin) {
			++itmp1;
			d__1 = tmp2, d__2 = -(*pivmin);
			tmp2 = (d__1<d__2) ? d__1 : d__2;
		    }
		}

		if (*ijob <= 2) {

		    i__5 = nab[ji + nab_dim1];
		    i__3 = nab[ji + (nab_dim1 << 1)];
		    i__4 = (i__5>itmp1) ? i__5 : itmp1;
		    itmp1 = (i__3<i__4) ? i__3 : i__4;

		    if (itmp1 == nab[ji + (nab_dim1 << 1)]) {

			ab[ji + (ab_dim1 << 1)] = tmp1;

		    } else if (itmp1 == nab[ji + nab_dim1]) {

			ab[ji + ab_dim1] = tmp1;
		    } else if (klnew < *mmax) {

			++klnew;
			ab[klnew + (ab_dim1 << 1)] = ab[ji + (ab_dim1 << 1)];
			nab[klnew + (nab_dim1 << 1)] = nab[ji + (nab_dim1 << 
				1)];
			ab[klnew + ab_dim1] = tmp1;
			nab[klnew + nab_dim1] = itmp1;
			ab[ji + (ab_dim1 << 1)] = tmp1;
			nab[ji + (nab_dim1 << 1)] = itmp1;
		    } else {
			*info = *mmax + 1;
			return;
		    }
		} else {

		    if (itmp1 <= nval[ji]) {
			ab[ji + ab_dim1] = tmp1;
			nab[ji + nab_dim1] = itmp1;
		    }
		    if (itmp1 >= nval[ji]) {
			ab[ji + (ab_dim1 << 1)] = tmp1;
			nab[ji + (nab_dim1 << 1)] = itmp1;
		    }
		}
	    }
	    kl = klnew;

	}

	kfnew = kf;
	i__2 = kl;
	for (ji = kf; ji <= i__2; ++ji) {
	    tmp1 = std::abs(ab[ji + (ab_dim1 << 1)] - ab[ji + ab_dim1]);
	    d__3 = std::abs(ab[ji + (ab_dim1 << 1)]);
	    d__4 = std::abs(ab[ji + ab_dim1]);
	    tmp2 = (d__3>d__4) ? d__3 : d__4;
	    d__1 = (*abstol>*pivmin) ? *abstol : *pivmin;
	    d__2 = *reltol * tmp2;
	    if (tmp1 < ((d__1>d__2) ? d__1 : d__2) || nab[ji + nab_dim1] >= nab[ji + (
		    nab_dim1 << 1)]) {

		if (ji > kfnew) {
		    tmp1 = ab[ji + ab_dim1];
		    tmp2 = ab[ji + (ab_dim1 << 1)];
		    itmp1 = nab[ji + nab_dim1];
		    itmp2 = nab[ji + (nab_dim1 << 1)];
		    ab[ji + ab_dim1] = ab[kfnew + ab_dim1];
		    ab[ji + (ab_dim1 << 1)] = ab[kfnew + (ab_dim1 << 1)];
		    nab[ji + nab_dim1] = nab[kfnew + nab_dim1];
		    nab[ji + (nab_dim1 << 1)] = nab[kfnew + (nab_dim1 << 1)];
		    ab[kfnew + ab_dim1] = tmp1;
		    ab[kfnew + (ab_dim1 << 1)] = tmp2;
		    nab[kfnew + nab_dim1] = itmp1;
		    nab[kfnew + (nab_dim1 << 1)] = itmp2;
		    if (*ijob == 3) {
			itmp1 = nval[ji];
			nval[ji] = nval[kfnew];
			nval[kfnew] = itmp1;
		    }
		}
		++kfnew;
	    }
	}
	kf = kfnew;

	i__2 = kl;
	for (ji = kf; ji <= i__2; ++ji) {
	    c__[ji] = (ab[ji + ab_dim1] + ab[ji + (ab_dim1 << 1)]) * .5;
	}

	if (kf > kl) {
	    break;
	}
    }

    i__1 = kl + 1 - kf;
    if(i__1>0)
      *info = i__1;

    *mout = kl;

    return;

}


