/* dlamch.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 "blaswrap.h"
#include "lapack_datatypes.h"

/* Table of constant values */

/* static integer c__1 = 1; */
static doublereal c_b32 = 0.;

static inline doublereal pow_di(doublereal *ap, integer *bp) {
  doublereal pow, x;
  integer n;
  unsigned long u;

  pow = 1;
  x = *ap;
  n = *bp;

  if (n != 0) {
    if (n < 0) {
      n = -n;
      x = 1 / x;
    }
    for (u = n;;) {
      if (u & 01) pow *= x;
      if (u >>= 1)
        x *= x;
      else
        break;
    }
  }
  return (pow);
}

doublereal dlamch_(char *cmach) {
  /* Initialized data */

  static logical first = TRUE_;

  /* System generated locals */
  integer i__1;
  doublereal ret_val;

  /* Local variables */
  static doublereal t;
  integer it;
  static doublereal rnd, eps, base;
  integer beta;
  static doublereal emin, prec, emax;
  integer imin, imax;
  logical lrnd = 0;
  static doublereal rmin, rmax;
  doublereal rmach = 0;
  extern logical lsame_(char *, char *);
  doublereal small;
  static doublereal sfmin;
  extern /* Subroutine */ void dlamc2_(integer *, integer *, logical *, doublereal *, integer *, doublereal *,
                                       integer *, doublereal *);

  /*  -- LAPACK auxiliary routine (version 3.2) -- */
  /*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
  /*     November 2006 */

  /*     .. Scalar Arguments .. */
  /*     .. */

  /*  Purpose */
  /*  ======= */

  /*  DLAMCH determines double precision machine parameters. */

  /*  Arguments */
  /*  ========= */

  /*  CMACH   (input) CHARACTER*1 */
  /*          Specifies the value to be returned by DLAMCH: */
  /*          = 'E' or 'e',   DLAMCH := eps */
  /*          = 'S' or 's ,   DLAMCH := sfmin */
  /*          = 'B' or 'b',   DLAMCH := base */
  /*          = 'P' or 'p',   DLAMCH := eps*base */
  /*          = 'N' or 'n',   DLAMCH := t */
  /*          = 'R' or 'r',   DLAMCH := rnd */
  /*          = 'M' or 'm',   DLAMCH := emin */
  /*          = 'U' or 'u',   DLAMCH := rmin */
  /*          = 'L' or 'l',   DLAMCH := emax */
  /*          = 'O' or 'o',   DLAMCH := rmax */

  /*          where */

  /*          eps   = relative machine precision */
  /*          sfmin = safe minimum, such that 1/sfmin does not overflow */
  /*          base  = base of the machine */
  /*          prec  = eps*base */
  /*          t     = number of (base) digits in the mantissa */
  /*          rnd   = 1.0 when rounding occurs in addition, 0.0 otherwise */
  /*          emin  = minimum exponent before (gradual) underflow */
  /*          rmin  = underflow threshold - base**(emin-1) */
  /*          emax  = largest exponent before overflow */
  /*          rmax  = overflow threshold  - (base**emax)*(1-eps) */

  /* ===================================================================== */

  /*     .. Parameters .. */
  /*     .. */
  /*     .. Local Scalars .. */
  /*     .. */
  /*     .. External Functions .. */
  /*     .. */
  /*     .. External Subroutines .. */
  /*     .. */
  /*     .. Save statement .. */
  /*     .. */
  /*     .. Data statements .. */
  /*     .. */
  /*     .. Executable Statements .. */

  if (first) {
    dlamc2_(&beta, &it, &lrnd, &eps, &imin, &rmin, &imax, &rmax);
    base = (doublereal)beta;
    t = (doublereal)it;
    if (lrnd) {
      rnd = 1.;
      i__1 = 1 - it;
      eps = pow_di(&base, &i__1) / 2;
    } else {
      rnd = 0.;
      i__1 = 1 - it;
      eps = pow_di(&base, &i__1);
    }
    prec = eps * base;
    emin = (doublereal)imin;
    emax = (doublereal)imax;
    sfmin = rmin;
    small = 1. / rmax;
    if (small >= sfmin) {
      /*           Use SMALL plus a bit, to avoid the possibility of rounding */
      /*           causing overflow when computing  1/sfmin. */

      sfmin = small * (eps + 1.);
    }
  }

  if (lsame_(cmach, "E")) {
    rmach = eps;
  } else if (lsame_(cmach, "S")) {
    rmach = sfmin;
  } else if (lsame_(cmach, "B")) {
    rmach = base;
  } else if (lsame_(cmach, "P")) {
    rmach = prec;
  } else if (lsame_(cmach, "N")) {
    rmach = t;
  } else if (lsame_(cmach, "R")) {
    rmach = rnd;
  } else if (lsame_(cmach, "M")) {
    rmach = emin;
  } else if (lsame_(cmach, "U")) {
    rmach = rmin;
  } else if (lsame_(cmach, "L")) {
    rmach = emax;
  } else if (lsame_(cmach, "O")) {
    rmach = rmax;
  }

  ret_val = rmach;
  first = FALSE_;
  return ret_val;

  /*     End of DLAMCH */

} /* dlamch_ */

/* *********************************************************************** */

/* Subroutine */ void dlamc1_(integer *beta, integer *t, logical *rnd, logical *ieee1) {
  /* Initialized data */

  static logical first = TRUE_;

  /* System generated locals */
  doublereal d__1, d__2;

  /* Local variables */
  doublereal a, b, c__, f, t1, t2;
  static integer lt;
  doublereal one, qtr;
  static logical lrnd;
  static integer lbeta;
  doublereal savec;
  extern doublereal dlamc3_(doublereal *, doublereal *);
  static logical lieee1;

  /*  -- LAPACK auxiliary routine (version 3.2) -- */
  /*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
  /*     November 2006 */

  /*     .. Scalar Arguments .. */
  /*     .. */

  /*  Purpose */
  /*  ======= */

  /*  DLAMC1 determines the machine parameters given by BETA, T, RND, and */
  /*  IEEE1. */

  /*  Arguments */
  /*  ========= */

  /*  BETA    (output) INTEGER */
  /*          The base of the machine. */

  /*  T       (output) INTEGER */
  /*          The number of ( BETA ) digits in the mantissa. */

  /*  RND     (output) LOGICAL */
  /*          Specifies whether proper rounding  ( RND = .TRUE. )  or */
  /*          chopping  ( RND = .FALSE. )  occurs in addition. This may not */
  /*          be a reliable guide to the way in which the machine performs */
  /*          its arithmetic. */

  /*  IEEE1   (output) LOGICAL */
  /*          Specifies whether rounding appears to be done in the IEEE */
  /*          'round to nearest' style. */

  /*  Further Details */
  /*  =============== */

  /*  The routine is based on the routine  ENVRON  by Malcolm and */
  /*  incorporates suggestions by Gentleman and Marovich. See */

  /*     Malcolm M. A. (1972) Algorithms to reveal properties of */
  /*        floating-point arithmetic. Comms. of the ACM, 15, 949-951. */

  /*     Gentleman W. M. and Marovich S. B. (1974) More on algorithms */
  /*        that reveal properties of floating point arithmetic units. */
  /*        Comms. of the ACM, 17, 276-277. */

  /* ===================================================================== */

  /*     .. Local Scalars .. */
  /*     .. */
  /*     .. External Functions .. */
  /*     .. */
  /*     .. Save statement .. */
  /*     .. */
  /*     .. Data statements .. */
  /*     .. */
  /*     .. Executable Statements .. */

  if (first) {
    one = 1.;

    /*        LBETA,  LIEEE1,  LT and  LRND  are the  local values  of  BETA, */
    /*        IEEE1, T and RND. */

    /*        Throughout this routine  we use the function  DLAMC3  to ensure */
    /*        that relevant values are  stored and not held in registers,  or */
    /*        are not affected by optimizers. */

    /*        Compute  a = 2.0**m  with the  smallest positive integer m such */
    /*        that */

    /*           fl( a + 1.0 ) = a. */

    a = 1.;
    c__ = 1.;

  /* +       WHILE( C.EQ.ONE )LOOP */
  L10:
    if (c__ == one) {
      a *= 2;
      c__ = dlamc3_(&a, &one);
      d__1 = -a;
      c__ = dlamc3_(&c__, &d__1);
      goto L10;
    }
    /* +       END WHILE */

    /*        Now compute  b = 2.0**m  with the smallest positive integer m */
    /*        such that */

    /*           fl( a + b ) .gt. a. */

    b = 1.;
    c__ = dlamc3_(&a, &b);

  /* +       WHILE( C.EQ.A )LOOP */
  L20:
    if (c__ == a) {
      b *= 2;
      c__ = dlamc3_(&a, &b);
      goto L20;
    }
    /* +       END WHILE */

    /*        Now compute the base.  a and c  are neighbouring floating point */
    /*        numbers  in the  interval  ( beta**t, beta**( t + 1 ) )  and so */
    /*        their difference is beta. Adding 0.25 to c is to ensure that it */
    /*        is truncated to beta and not ( beta - 1 ). */

    qtr = one / 4;
    savec = c__;
    d__1 = -a;
    c__ = dlamc3_(&c__, &d__1);
    lbeta = (integer)(c__ + qtr);

    /*        Now determine whether rounding or chopping occurs,  by adding a */
    /*        bit  less  than  beta/2  and a  bit  more  than  beta/2  to  a. */

    b = (doublereal)lbeta;
    d__1 = b / 2;
    d__2 = -b / 100;
    f = dlamc3_(&d__1, &d__2);
    c__ = dlamc3_(&f, &a);
    if (c__ == a) {
      lrnd = TRUE_;
    } else {
      lrnd = FALSE_;
    }
    d__1 = b / 2;
    d__2 = b / 100;
    f = dlamc3_(&d__1, &d__2);
    c__ = dlamc3_(&f, &a);
    if (lrnd && c__ == a) {
      lrnd = FALSE_;
    }

    /*        Try and decide whether rounding is done in the  IEEE  'round to */
    /*        nearest' style. B/2 is half a unit in the last place of the two */
    /*        numbers A and SAVEC. Furthermore, A is even, i.e. has last  bit */
    /*        zero, and SAVEC is odd. Thus adding B/2 to A should not  change */
    /*        A, but adding B/2 to SAVEC should change SAVEC. */

    d__1 = b / 2;
    t1 = dlamc3_(&d__1, &a);
    d__1 = b / 2;
    t2 = dlamc3_(&d__1, &savec);
    lieee1 = t1 == a && t2 > savec && lrnd;

    /*        Now find  the  mantissa, t.  It should  be the  integer part of */
    /*        log to the base beta of a,  however it is safer to determine  t */
    /*        by powering.  So we find t as the smallest positive integer for */
    /*        which */

    /*           fl( beta**t + 1.0 ) = 1.0. */

    lt = 0;
    a = 1.;
    c__ = 1.;

  /* +       WHILE( C.EQ.ONE )LOOP */
  L30:
    if (c__ == one) {
      ++lt;
      a *= lbeta;
      c__ = dlamc3_(&a, &one);
      d__1 = -a;
      c__ = dlamc3_(&c__, &d__1);
      goto L30;
    }
    /* +       END WHILE */
  }

  *beta = lbeta;
  *t = lt;
  *rnd = lrnd;
  *ieee1 = lieee1;
  first = FALSE_;

  /*     End of DLAMC1 */

} /* dlamc1_ */

/* *********************************************************************** */

/* Subroutine */ void dlamc2_(integer *beta, integer *t, logical *rnd, doublereal *eps, integer *emin, doublereal *rmin,
                              integer *emax, doublereal *rmax) {
  /* Initialized data */

  static logical first = TRUE_;
  static logical iwarn = FALSE_;

  /* Format strings */
  /*
  static char fmt_9999[] =
      "(//\002 WARNING. The value EMIN may be incorre"
      "ct:-\002,\002  EMIN = \002,i8,/\002 If, after inspection, the va"
      "lue EMIN looks\002,\002 acceptable please comment out \002,/\002"
      " the IF block as marked within the code of routine\002,\002 DLAM"
      "C2,\002,/\002 otherwise supply EMIN explicitly.\002,/)";
  */
  /* System generated locals */
  integer i__1;
  doublereal d__1, d__2, d__3, d__4, d__5;

  /* Builtin functions */
  /* integer s_wsfe(cilist *), do_fio(integer *, char *, ftnlen), e_wsfe(void); */

  /* Local variables */
  doublereal a, b, c__;
  integer i__;
  static integer lt;
  doublereal one, two;
  logical ieee;
  doublereal half;
  logical lrnd = 0;
  static doublereal leps;
  doublereal zero;
  static integer lbeta;
  doublereal rbase;
  static integer lemin, lemax;
  integer gnmin;
  doublereal small;
  integer gpmin;
  doublereal third;
  static doublereal lrmin, lrmax;
  doublereal sixth;
  extern /* Subroutine */ void dlamc1_(integer *, integer *, logical *, logical *);
  extern doublereal dlamc3_(doublereal *, doublereal *);
  logical lieee1;
  extern /* Subroutine */ void dlamc4_(integer *, doublereal *, integer *),
      dlamc5_(integer *, integer *, integer *, logical *, integer *, doublereal *);
  integer ngnmin, ngpmin;

  /* Fortran I/O blocks */
  /* static cilist io___58 = {0, 6, 0, fmt_9999, 0}; */

  /*  -- LAPACK auxiliary routine (version 3.2) -- */
  /*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
  /*     November 2006 */

  /*     .. Scalar Arguments .. */
  /*     .. */

  /*  Purpose */
  /*  ======= */

  /*  DLAMC2 determines the machine parameters specified in its argument */
  /*  list. */

  /*  Arguments */
  /*  ========= */

  /*  BETA    (output) INTEGER */
  /*          The base of the machine. */

  /*  T       (output) INTEGER */
  /*          The number of ( BETA ) digits in the mantissa. */

  /*  RND     (output) LOGICAL */
  /*          Specifies whether proper rounding  ( RND = .TRUE. )  or */
  /*          chopping  ( RND = .FALSE. )  occurs in addition. This may not */
  /*          be a reliable guide to the way in which the machine performs */
  /*          its arithmetic. */

  /*  EPS     (output) DOUBLE PRECISION */
  /*          The smallest positive number such that */

  /*             fl( 1.0 - EPS ) .LT. 1.0, */

  /*          where fl denotes the computed value. */

  /*  EMIN    (output) INTEGER */
  /*          The minimum exponent before (gradual) underflow occurs. */

  /*  RMIN    (output) DOUBLE PRECISION */
  /*          The smallest normalized number for the machine, given by */
  /*          BASE**( EMIN - 1 ), where  BASE  is the floating point value */
  /*          of BETA. */

  /*  EMAX    (output) INTEGER */
  /*          The maximum exponent before overflow occurs. */

  /*  RMAX    (output) DOUBLE PRECISION */
  /*          The largest positive number for the machine, given by */
  /*          BASE**EMAX * ( 1 - EPS ), where  BASE  is the floating point */
  /*          value of BETA. */

  /*  Further Details */
  /*  =============== */

  /*  The computation of  EPS  is based on a routine PARANOIA by */
  /*  W. Kahan of the University of California at Berkeley. */

  /* ===================================================================== */

  /*     .. Local Scalars .. */
  /*     .. */
  /*     .. External Functions .. */
  /*     .. */
  /*     .. External Subroutines .. */
  /*     .. */
  /*     .. Intrinsic Functions .. */
  /*     .. */
  /*     .. Save statement .. */
  /*     .. */
  /*     .. Data statements .. */
  /*     .. */
  /*     .. Executable Statements .. */

  if (first) {
    zero = 0.;
    one = 1.;
    two = 2.;

    /*        LBETA, LT, LRND, LEPS, LEMIN and LRMIN  are the local values of */
    /*        BETA, T, RND, EPS, EMIN and RMIN. */

    /*        Throughout this routine  we use the function  DLAMC3  to ensure */
    /*        that relevant values are stored  and not held in registers,  or */
    /*        are not affected by optimizers. */

    /*        DLAMC1 returns the parameters  LBETA, LT, LRND and LIEEE1. */

    dlamc1_(&lbeta, &lt, &lrnd, &lieee1);

    /*        Start to find EPS. */

    b = (doublereal)lbeta;
    i__1 = -lt;
    a = pow_di(&b, &i__1);
    leps = a;

    /*        Try some tricks to see whether or not this is the correct  EPS. */

    b = two / 3;
    half = one / 2;
    d__1 = -half;
    sixth = dlamc3_(&b, &d__1);
    third = dlamc3_(&sixth, &sixth);
    d__1 = -half;
    b = dlamc3_(&third, &d__1);
    b = dlamc3_(&b, &sixth);
    b = abs(b);
    if (b < leps) {
      b = leps;
    }

    leps = 1.;

  /* +       WHILE( ( LEPS.GT.B ).AND.( B.GT.ZERO ) )LOOP */
  L10:
    if (leps > b && b > zero) {
      leps = b;
      d__1 = half * leps;
      /* Computing 5th power */
      d__3 = two, d__4 = d__3, d__3 *= d__3;
      /* Computing 2nd power */
      d__5 = leps;
      d__2 = d__4 * (d__3 * d__3) * (d__5 * d__5);
      c__ = dlamc3_(&d__1, &d__2);
      d__1 = -c__;
      c__ = dlamc3_(&half, &d__1);
      b = dlamc3_(&half, &c__);
      d__1 = -b;
      c__ = dlamc3_(&half, &d__1);
      b = dlamc3_(&half, &c__);
      goto L10;
    }
    /* +       END WHILE */

    if (a < leps) {
      leps = a;
    }

    /*        Computation of EPS complete. */

    /*        Now find  EMIN.  Let A = + or - 1, and + or - (1 + BASE**(-3)). */
    /*        Keep dividing  A by BETA until (gradual) underflow occurs. This */
    /*        is detected when we cannot recover the previous A. */

    rbase = one / lbeta;
    small = one;
    for (i__ = 1; i__ <= 3; ++i__) {
      d__1 = small * rbase;
      small = dlamc3_(&d__1, &zero);
      /* L20: */
    }
    a = dlamc3_(&one, &small);
    dlamc4_(&ngpmin, &one, &lbeta);
    d__1 = -one;
    dlamc4_(&ngnmin, &d__1, &lbeta);
    dlamc4_(&gpmin, &a, &lbeta);
    d__1 = -a;
    dlamc4_(&gnmin, &d__1, &lbeta);
    ieee = FALSE_;

    if (ngpmin == ngnmin && gpmin == gnmin) {
      if (ngpmin == gpmin) {
        lemin = ngpmin;
        /*            ( Non twos-complement machines, no gradual underflow; */
        /*              e.g.,  VAX ) */
      } else if (gpmin - ngpmin == 3) {
        lemin = ngpmin - 1 + lt;
        ieee = TRUE_;
        /*            ( Non twos-complement machines, with gradual underflow; */
        /*              e.g., IEEE standard followers ) */
      } else {
        lemin = min(ngpmin, gpmin);
        /*            ( A guess; no known machine ) */
        iwarn = TRUE_;
      }

    } else if (ngpmin == gpmin && ngnmin == gnmin) {
      if ((i__1 = ngpmin - ngnmin, abs(i__1)) == 1) {
        lemin = max(ngpmin, ngnmin);
        /*            ( Twos-complement machines, no gradual underflow; */
        /*              e.g., CYBER 205 ) */
      } else {
        lemin = min(ngpmin, ngnmin);
        /*            ( A guess; no known machine ) */
        iwarn = TRUE_;
      }

    } else if ((i__1 = ngpmin - ngnmin, abs(i__1)) == 1 && gpmin == gnmin) {
      if (gpmin - min(ngpmin, ngnmin) == 3) {
        lemin = max(ngpmin, ngnmin) - 1 + lt;
        /*            ( Twos-complement machines with gradual underflow; */
        /*              no known machine ) */
      } else {
        lemin = min(ngpmin, ngnmin);
        /*            ( A guess; no known machine ) */
        iwarn = TRUE_;
      }

    } else {
      /* Computing MIN */
      i__1 = min(ngpmin, ngnmin), i__1 = min(i__1, gpmin);
      lemin = min(i__1, gnmin);
      /*         ( A guess; no known machine ) */
      iwarn = TRUE_;
    }
    first = FALSE_;
    /* ** */
    /* Comment out this if block if EMIN is ok */
    /*
    if (iwarn) {
      first = TRUE_;
      s_wsfe(&io___58);
      do_fio(&c__1, (char *)&lemin, (ftnlen)sizeof(integer));
      e_wsfe();
    }
    */
    /* ** */

    /*        Assume IEEE arithmetic if we found denormalised  numbers above, */
    /*        or if arithmetic seems to round in the  IEEE style,  determined */
    /*        in routine DLAMC1. A true IEEE machine should have both  things */
    /*        true; however, faulty machines may have one or the other. */

    ieee = ieee || lieee1;

    /*        Compute  RMIN by successive division by  BETA. We could compute */
    /*        RMIN as BASE**( EMIN - 1 ),  but some machines underflow during */
    /*        this computation. */

    lrmin = 1.;
    i__1 = 1 - lemin;
    for (i__ = 1; i__ <= i__1; ++i__) {
      d__1 = lrmin * rbase;
      lrmin = dlamc3_(&d__1, &zero);
      /* L30: */
    }

    /*        Finally, call DLAMC5 to compute EMAX and RMAX. */

    dlamc5_(&lbeta, &lt, &lemin, &ieee, &lemax, &lrmax);
  }

  *beta = lbeta;
  *t = lt;
  *rnd = lrnd;
  *eps = leps;
  *emin = lemin;
  *rmin = lrmin;
  *emax = lemax;
  *rmax = lrmax;

  /*     End of DLAMC2 */

} /* dlamc2_ */

/* *********************************************************************** */

doublereal dlamc3_(doublereal *a, doublereal *b) {
  /* System generated locals */
  doublereal ret_val;

  /*  -- LAPACK auxiliary routine (version 3.2) -- */
  /*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
  /*     November 2006 */

  /*     .. Scalar Arguments .. */
  /*     .. */

  /*  Purpose */
  /*  ======= */

  /*  DLAMC3  is intended to force  A  and  B  to be stored prior to doing */
  /*  the addition of  A  and  B ,  for use in situations where optimizers */
  /*  might hold one of these in a register. */

  /*  Arguments */
  /*  ========= */

  /*  A       (input) DOUBLE PRECISION */
  /*  B       (input) DOUBLE PRECISION */
  /*          The values A and B. */

  /* ===================================================================== */

  /*     .. Executable Statements .. */

  ret_val = *a + *b;

  return ret_val;

  /*     End of DLAMC3 */

} /* dlamc3_ */

/* *********************************************************************** */

/* Subroutine */ void dlamc4_(integer *emin, doublereal *start, integer *base) {
  /* System generated locals */
  integer i__1;
  doublereal d__1;

  /* Local variables */
  doublereal a;
  integer i__;
  doublereal b1, b2, c1, c2, d1, d2, one, zero, rbase;
  extern doublereal dlamc3_(doublereal *, doublereal *);

  /*  -- LAPACK auxiliary routine (version 3.2) -- */
  /*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
  /*     November 2006 */

  /*     .. Scalar Arguments .. */
  /*     .. */

  /*  Purpose */
  /*  ======= */

  /*  DLAMC4 is a service routine for DLAMC2. */

  /*  Arguments */
  /*  ========= */

  /*  EMIN    (output) INTEGER */
  /*          The minimum exponent before (gradual) underflow, computed by */
  /*          setting A = START and dividing by BASE until the previous A */
  /*          can not be recovered. */

  /*  START   (input) DOUBLE PRECISION */
  /*          The starting point for determining EMIN. */

  /*  BASE    (input) INTEGER */
  /*          The base of the machine. */

  /* ===================================================================== */

  /*     .. Local Scalars .. */
  /*     .. */
  /*     .. External Functions .. */
  /*     .. */
  /*     .. Executable Statements .. */

  a = *start;
  one = 1.;
  rbase = one / *base;
  zero = 0.;
  *emin = 1;
  d__1 = a * rbase;
  b1 = dlamc3_(&d__1, &zero);
  c1 = a;
  c2 = a;
  d1 = a;
  d2 = a;
/* +    WHILE( ( C1.EQ.A ).AND.( C2.EQ.A ).AND. */
/*    $       ( D1.EQ.A ).AND.( D2.EQ.A )      )LOOP */
L10:
  if (c1 == a && c2 == a && d1 == a && d2 == a) {
    --(*emin);
    a = b1;
    d__1 = a / *base;
    b1 = dlamc3_(&d__1, &zero);
    d__1 = b1 * *base;
    c1 = dlamc3_(&d__1, &zero);
    d1 = zero;
    i__1 = *base;
    for (i__ = 1; i__ <= i__1; ++i__) {
      d1 += b1;
      /* L20: */
    }
    d__1 = a * rbase;
    b2 = dlamc3_(&d__1, &zero);
    d__1 = b2 / rbase;
    c2 = dlamc3_(&d__1, &zero);
    d2 = zero;
    i__1 = *base;
    for (i__ = 1; i__ <= i__1; ++i__) {
      d2 += b2;
      /* L30: */
    }
    goto L10;
  }
  /* +    END WHILE */

  /*     End of DLAMC4 */

} /* dlamc4_ */

/* *********************************************************************** */

/* Subroutine */ void dlamc5_(integer *beta, integer *p, integer *emin, logical *ieee, integer *emax,
                              doublereal *rmax) {
  /* System generated locals */
  integer i__1;
  doublereal d__1;

  /* Local variables */
  integer i__;
  doublereal y, z__;
  integer try__, lexp;
  doublereal oldy;
  integer uexp, nbits;
  extern doublereal dlamc3_(doublereal *, doublereal *);
  doublereal recbas;
  integer exbits, expsum;

  /*  -- LAPACK auxiliary routine (version 3.2) -- */
  /*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
  /*     November 2006 */

  /*     .. Scalar Arguments .. */
  /*     .. */

  /*  Purpose */
  /*  ======= */

  /*  DLAMC5 attempts to compute RMAX, the largest machine floating-point */
  /*  number, without overflow.  It assumes that EMAX + abs(EMIN) sum */
  /*  approximately to a power of 2.  It will fail on machines where this */
  /*  assumption does not hold, for example, the Cyber 205 (EMIN = -28625, */
  /*  EMAX = 28718).  It will also fail if the value supplied for EMIN is */
  /*  too large (i.e. too close to zero), probably with overflow. */

  /*  Arguments */
  /*  ========= */

  /*  BETA    (input) INTEGER */
  /*          The base of floating-point arithmetic. */

  /*  P       (input) INTEGER */
  /*          The number of base BETA digits in the mantissa of a */
  /*          floating-point value. */

  /*  EMIN    (input) INTEGER */
  /*          The minimum exponent before (gradual) underflow. */

  /*  IEEE    (input) LOGICAL */
  /*          A logical flag specifying whether or not the arithmetic */
  /*          system is thought to comply with the IEEE standard. */

  /*  EMAX    (output) INTEGER */
  /*          The largest exponent before overflow */

  /*  RMAX    (output) DOUBLE PRECISION */
  /*          The largest machine floating-point number. */

  /* ===================================================================== */

  /*     .. Parameters .. */
  /*     .. */
  /*     .. Local Scalars .. */
  /*     .. */
  /*     .. External Functions .. */
  /*     .. */
  /*     .. Intrinsic Functions .. */
  /*     .. */
  /*     .. Executable Statements .. */

  /*     First compute LEXP and UEXP, two powers of 2 that bound */
  /*     abs(EMIN). We then assume that EMAX + abs(EMIN) will sum */
  /*     approximately to the bound that is closest to abs(EMIN). */
  /*     (EMAX is the exponent of the required number RMAX). */

  lexp = 1;
  exbits = 1;
L10:
  try__ = lexp << 1;
  if (try__ <= -(*emin)) {
    lexp = try__;
    ++exbits;
    goto L10;
  }
  if (lexp == -(*emin)) {
    uexp = lexp;
  } else {
    uexp = try__;
    ++exbits;
  }

  /*     Now -LEXP is less than or equal to EMIN, and -UEXP is greater */
  /*     than or equal to EMIN. EXBITS is the number of bits needed to */
  /*     store the exponent. */

  if (uexp + *emin > -lexp - *emin) {
    expsum = lexp << 1;
  } else {
    expsum = uexp << 1;
  }

  /*     EXPSUM is the exponent range, approximately equal to */
  /*     EMAX - EMIN + 1 . */

  *emax = expsum + *emin - 1;
  nbits = exbits + 1 + *p;

  /*     NBITS is the total number of bits needed to store a */
  /*     floating-point number. */

  if (nbits % 2 == 1 && *beta == 2) {
    /*        Either there are an odd number of bits used to store a */
    /*        floating-point number, which is unlikely, or some bits are */
    /*        not used in the representation of numbers, which is possible, */
    /*        (e.g. Cray machines) or the mantissa has an implicit bit, */
    /*        (e.g. IEEE machines, Dec Vax machines), which is perhaps the */
    /*        most likely. We have to assume the last alternative. */
    /*        If this is true, then we need to reduce EMAX by one because */
    /*        there must be some way of representing zero in an implicit-bit */
    /*        system. On machines like Cray, we are reducing EMAX by one */
    /*        unnecessarily. */

    --(*emax);
  }

  if (*ieee) {
    /*        Assume we are on an IEEE machine which reserves one exponent */
    /*        for infinity and NaN. */

    --(*emax);
  }

  /*     Now create RMAX, the largest machine number, which should */
  /*     be equal to (1.0 - BETA**(-P)) * BETA**EMAX . */

  /*     First compute 1.0 - BETA**(-P), being careful that the */
  /*     result is less than 1.0 . */

  recbas = 1. / *beta;
  z__ = *beta - 1.;
  y = 0.;
  i__1 = *p;
  for (i__ = 1; i__ <= i__1; ++i__) {
    z__ *= recbas;
    if (y < 1.) {
      oldy = y;
    }
    y = dlamc3_(&y, &z__);
    /* L20: */
  }
  if (y >= 1.) {
    y = oldy;
  }

  /*     Now multiply by BETA**EMAX to get RMAX. */

  i__1 = *emax;
  for (i__ = 1; i__ <= i__1; ++i__) {
    d__1 = y * *beta;
    y = dlamc3_(&d__1, &c_b32);
    /* L30: */
  }

  *rmax = y;

  /*     End of DLAMC5 */

} /* dlamc5_ */