/home66/gary/public_html/cloudy/c08_branch/source/temp_change.cpp

Go to the documentation of this file.

/* This file is part of Cloudy and is copyright (C)1978-2008 by Gary J. Ferland and
 * others.  For conditions of distribution and use see copyright notice in license.txt */
/*tfidle update some temperature dependent variables */
/*tauff compute optical depth where cloud is thin to free-free and plasma freq */
/*velset set thermal velocities for all particles in gas */
#include "cddefines.h"
#include "physconst.h"
#include "opacity.h"
#include "iso.h"
#include "dense.h"
#include "phycon.h"
#include "stopcalc.h"
#include "continuum.h"
#include "trace.h"
#include "rfield.h"
#include "doppvel.h"
#include "radius.h"
#include "wind.h"
#include "thermal.h"

/*tauff compute optical depth where cloud is thin to free-free and plasma freq */
STATIC void tauff(void);
/*velset set thermal velocities for all particles in gas */
STATIC void velset(void);
/* On first run, fill GauntFF with gaunt factors        */
STATIC void FillGFF(void);
/* Interpolate on GauntFF to calc gaunt at current temp, phycon.te      */
STATIC realnum InterpolateGff( long charge , double ERyd );
STATIC int LinterpTable(realnum **t, realnum *v, long int lta, long int ltb, realnum x, realnum *a, long int *pipx);
STATIC int LinterpVector(realnum **t, realnum *v, long lta , long ltb, realnum *yy , long ny, realnum **a);
STATIC void fhunt(realnum *xx, long int n, realnum x, long int *j);

STATIC void tfidle(
                        bool lgForceUpdate);

static long lgGffNotFilled = true;

const long N_TE_GFF = 21;
const long N_PHOTON_GFF = 145;  /* log(photon energy) = -8 to 10 in one-eighth dec steps        */
static realnum ***GauntFF;
static realnum **GauntFF_T;
/* the array of logs of temperatures at which GauntFF is defined */
static realnum TeGFF[N_TE_GFF];
/* the array of logs of u at which GauntFF is defined   */
static realnum PhoGFF[N_PHOTON_GFF];

void TempChange(
                         double TempNew ,
                         /* option to force update of all variables */
                         bool lgForceUpdate)
{

        DEBUG_ENTRY( "TempChange()" );

        /* set new temperature */
        if( TempNew >= phycon.TEMP_LIMIT_HIGH )
        {
                /* temp is too high */
                fprintf(ioQQQ," PROBLEM DISASTER - the kinetic temperature, %.3eK,"
                        " is above the upper limit of the code, %.3eK.\n",
                        TempNew , phycon.TEMP_LIMIT_HIGH );
                fprintf(ioQQQ," This calculation is aborting.\n Sorry.\n");

                TempNew = phycon.TEMP_LIMIT_HIGH*0.999;
                lgAbort = true;
        }
        else if( TempNew <= phycon.TEMP_LIMIT_LOW )
        {
                /* temp is too low */
                fprintf(ioQQQ," PROBLEM DISASTER - the kinetic temperature, %.3eK,"
                        " is below the lower limit of the code, %.3eK.\n",
                        TempNew , phycon.TEMP_LIMIT_LOW );
                fprintf(ioQQQ," This calculation is aborting.\n Sorry.\n");
                TempNew = phycon.TEMP_LIMIT_LOW*1.0001;
                lgAbort = true;
        }
        else if( TempNew < StopCalc.TeFloor )
        {
                /* temperature floor option  -
                 * go to constant temperature calculation if temperature
                 * falls below floor */
                thermal.lgTemperatureConstant = true;
                thermal.ConstTemp = (realnum)StopCalc.TeFloor;
                phycon.te = thermal.ConstTemp;
                /*fprintf(ioQQQ,"DEBUG TempChange hit temp floor, setting const temp to %.3e\n",
                        phycon.te );*/
        }
        else
        {
                /* temp is within range */
                phycon.te = TempNew;
        }

        /* now update related variables */
        tfidle( lgForceUpdate );
        return;
}
void TempChange(
                                double TempNew )
{

        DEBUG_ENTRY( "TempChange()" );

        /* set new temperature */
        if( TempNew >= phycon.TEMP_LIMIT_HIGH )
        {
                /* temp is too high */
                fprintf(ioQQQ," PROBLEM DISASTER - the kinetic temperature, %.3eK,"
                        " is above the upper limit of the code, %.3eK.\n",
                        TempNew , phycon.TEMP_LIMIT_HIGH );
                fprintf(ioQQQ," This calculation is aborting.\n Sorry.\n");

                TempNew = phycon.TEMP_LIMIT_HIGH*0.999;
        }
        else if( TempNew <= phycon.TEMP_LIMIT_LOW )
        {
                /* temp is too low */
                fprintf(ioQQQ," PROBLEM DISASTER - the kinetic temperature, %.3eK,"
                        " is below the lower limit of the code, %.3eK.\n",
                        TempNew , phycon.TEMP_LIMIT_LOW );
                fprintf(ioQQQ," This calculation is aborting.\n Sorry.\n");
                TempNew = phycon.TEMP_LIMIT_LOW*1.0001;
        }
        else
        {
                /* temp is within range */
                phycon.te = TempNew;
        }

        /* now update related variables */
        tfidle( false );
        return;
}

void tfidle(
        /* option to force update of all variables */
        bool lgForceUpdate)
{
        static double tgffused=-1., 
          tgffsued2=-1.;
        static long int nff_defined=-1;
        static long maxion = 0, oldmaxion = 0;
        static double ttused = 0.;
        static bool lgZLogSet = false;
        bool lgGauntF;
        long int ion;
        long int i,
          nelem,
          if1,
                ipTe,
                ret;
        double fac,  
          fanu;

        DEBUG_ENTRY( "tfidle()" );

        /* called with lgForceUpdate true in zero.c, when we must update everything */
        if( lgForceUpdate )
        {
                ttused = -1.;
                tgffused = -1.;
                tgffsued2 = -1.;
        }

        /* check that eden not negative */
        if( dense.eden <= 0. )
        {
                fprintf( ioQQQ, "tfidle called with a zero or negative electron density,%10.2e\n", 
                  dense.eden );
                TotalInsanity();
        }

        /* check that temperature not negative */
        if( phycon.te <= 0. )
        {
                fprintf( ioQQQ, "tfidle called with a negative electron temperature,%10.2e\n", 
                  phycon.te );
                TotalInsanity();
        }

        /* one time only, set up array of logs of charge squared */
        if( !lgZLogSet )
        {
                for( nelem=0; nelem<LIMELM; ++nelem )
                {
                        /* this array is used to modify the log temperature array
                         * defined below, for hydrogenic species of charge nelem+1 */
                        phycon.sqlogz[nelem] = log10( POW2(nelem+1.) );
                }
                lgZLogSet = true;
        }

        if( ! fp_equal( phycon.te, ttused ) )
        {
                ttused = phycon.te;
                thermal.te_update = phycon.te;
                /* current temperature in various units */
                phycon.te_eV = phycon.te/EVDEGK;
                phycon.te_ryd = phycon.te/TE1RYD;
                phycon.te_wn = phycon.te / T1CM;

                phycon.tesqrd = POW2(phycon.te);
                phycon.sqrte = sqrt(phycon.te);
                thermal.halfte = 0.5/phycon.te;
                thermal.tsq1 = 1./phycon.tesqrd;
                phycon.te32 = phycon.te*phycon.sqrte;
                phycon.teinv = 1./phycon.te;

                phycon.alogte = log10(phycon.te);
                phycon.alnte = log(phycon.te);

                phycon.telogn[0] = phycon.alogte;
                for( i=1; i < 7; i++ )
                {
                        phycon.telogn[i] = phycon.telogn[i-1]*phycon.telogn[0];
                }

                phycon.te10 = pow(phycon.te,0.10);
                phycon.te20 = phycon.te10 * phycon.te10;
                phycon.te30 = phycon.te20 * phycon.te10;
                phycon.te40 = phycon.te30 * phycon.te10;
                phycon.te70 = phycon.sqrte * phycon.te20;
                phycon.te90 = phycon.te70 * phycon.te20;

                phycon.te01 = pow(phycon.te,0.01);
                phycon.te02 = phycon.te01 * phycon.te01;
                phycon.te03 = phycon.te02 * phycon.te01;
                phycon.te04 = phycon.te02 * phycon.te02;
                phycon.te05 = phycon.te03 * phycon.te02;
                phycon.te07 = phycon.te05 * phycon.te02;

                phycon.te001 = pow(phycon.te,0.001);
                phycon.te002 = phycon.te001 * phycon.te001;
                phycon.te003 = phycon.te002 * phycon.te001;
                phycon.te004 = phycon.te002 * phycon.te002;
                phycon.te005 = phycon.te003 * phycon.te002;
                phycon.te007 = phycon.te005 * phycon.te002;
                /*>>>chng 06 June 30 -Humeshkar Nemala*/
                phycon.te0001 = pow(phycon.te ,0.0001);
                phycon.te0002 = phycon.te0001 * phycon.te0001;
                phycon.te0003 = phycon.te0002 * phycon.te0001;
                phycon.te0004 = phycon.te0002 * phycon.te0002;
                phycon.te0005 = phycon.te0003 * phycon.te0002;
                phycon.te0007 = phycon.te0005 * phycon.te0002;

        }

        /* >>>chng 99 nov 23, removed this line, so back to old method of h coll */
        /* used for hydrogenic collisions */
        /* 
         * following electron density has approximate correction for neutrals
         * corr of hi*1.7e-4 accounts for col ion by HI; 
         * >>refer      H0      correction for collisional contribution         Drawin, H.W. 1969, Zs Phys 225, 483.
         * also quoted in Dalgarno & McCray 1972
         * extensive discussion of this in 
         *>>refer       H0      collisions      Lambert, D.L. 
         * used EdenHCorr instead
         * edhi = eden + hi * 1.7e-4
         */
        dense.EdenHCorr = dense.eden + 
                /* dense.HCorrFac is unity by default and changed with the set HCOR command */
                dense.xIonDense[ipHYDROGEN][0]*1.7e-4 * dense.HCorrFac;

        /* this is parallel version for H0 onto H0 collisions - for now the same, but
         * this may not be correct */
        dense.EdenHontoHCorr = dense.EdenHCorr;

        /*>>chng 93 jun 04,
         * term with hi added June 4, 93, to account for warm pdr */
        /* >>chng 05 jan 05, Will Henney noticed that 1.e-4 used here is not same as
         * 1.7e-4 used for EdenHCorr, which had rewritten the expression.
         * change so that edensqte uses EdenHCorr rather than reevaluating */
        /*dense.edensqte = ((dense.eden + dense.xIonDense[ipHYDROGEN][0]/1e4)/phycon.sqrte);*/
        dense.edensqte = dense.EdenHCorr/phycon.sqrte;
        dense.cdsqte = dense.edensqte*COLL_CONST;
        dense.SqrtEden = sqrt(dense.eden);

        /* finally reset velocities */
        /* find line widths for thermal and turbulent motion
         * CLOUDY uses line center optical depths, =0.015 F / DELTA NU */
        velset();

        /* rest have to do with radiation field which may not be defined yet */
        if( !lgRfieldMalloced )
        {
                return;
        }

        /* correction factors for induced recombination, 
         * also used as Boltzmann factors
         * check for zero is because ContBoltz is zeroed out in initialization
         * of code, its possible this is a constant density grid of models
         * in which the code is called as a subroutine */
        /* >>chng 01 aug 21, must also test on size of continuum nflux because 
         * conintitemp can increase nflux then call this routine, although 
         * temp may not have changed */
        if( ! fp_equal(tgffused, phycon.te)
                || rfield.ContBoltz[0] <= 0. || nff_defined<rfield.nflux )
        {
                tgffused = phycon.te;
                fac = TE1RYD/phycon.te;
                i = 0;
                fanu = fac*rfield.anu[i];
                /* SEXP_LIMIT is 84 in cddefines.h - it is the -ln of smallest number
                 * that sexp can handle, and is used elsewhere in the code.  
                 * atom_level2 uses ContBoltz to see whether the rates will be significant.
                 * If the numbers did not agree then this test would be flawed, resulting in
                 * div by zero */
                while( i < rfield.nupper && fanu < SEXP_LIMIT )
                {
                        rfield.ContBoltz[i] = exp(-fanu);
                        ++i;
                        /* this is Boltzmann factor for NEXT cell */
                        fanu = fac*rfield.anu[i];
                }
                /* ipMaxBolt is number of cells defined, so defined up through ipMaxBolt-1 */
                rfield.ipMaxBolt = i;

                /* zero out remainder */
                /* >>chng 01 apr 14, upper limit has been ipMaxBolt+1, off by one */
                for( i=rfield.ipMaxBolt; i < rfield.nupper; i++ )
                {
                        rfield.ContBoltz[i] = 0.;
                }
        }

        /* find frequency where thin to bremsstrahlung or plasma frequency */
        tauff();

        oldmaxion = maxion;
        maxion = 0;

        /* Find highest maximum stage of ionization     */
        for( nelem = 0; nelem < LIMELM; nelem++ )
        {
                maxion = MAX2( maxion, dense.IonHigh[nelem] );
        }

        /* reevaluate if temperature or number of cells has changed
         * make sure the change is small enough that no big jumps in cooling occur */
        const double LIM = 0.02;
        if( fabs(1.-tgffsued2/phycon.te) > LIM || 
                /* this test - reevaluate if upper bound of defined values is
                 * above nflux, the highest point.  This only triggers in
                 * large grids when continuum source gets harder */
                nff_defined<rfield.nflux 
                /* this occurs when now have more stages of ionization than in previous defn */
                || maxion>oldmaxion )
        {
                static bool lgFirstRunDone = false;
                long lowion;
                /* >>chng 02 jan 10, only reevaluate needed states of ionization */
                if( fabs(1.-tgffsued2/phycon.te) <= LIM && nff_defined>=rfield.nflux && 
                        maxion>oldmaxion )
                {
                        /* this case temperature did not change by much, but upper
                         * stage of ionization increased.  only need to evaluate
                         * stages that have not been already done */
                        lowion = oldmaxion;
                }
                else
                {
                        /* temperature changed - do them all */
                        lowion = 1;
                }

                /* if1 will certainly be set to some positive value in gffsub */
                if1 = 1;

                /* chng 02 may 16, by Ryan...one gaunt factor array for all charges     */
                /* First index is EFFECTIVE CHARGE!     */
                /* highest stage of ionization is LIMELM, 
                 * index goes from 1 to LIMELM */

                nff_defined = rfield.nflux;

                ASSERT( if1 >= 0 );

                tgffsued2 = phycon.te;
                lgGauntF = true;

                /* new gaunt factors    */
                if( lgGffNotFilled )
                {
                        FillGFF();
                }

                if( lgFirstRunDone == false )
                {
                        maxion = LIMELM;
                        lgFirstRunDone = true;
                }

                /* >> chng 03 jan 23, rjrw -- move a couple of loops down into
                 * subroutines, and make those subroutines generic
                 * (i.e. dependences only on arguments, may be useful elsewhere...) */

                /* Make Gaunt table for new temperature */
                ipTe = -1;
                for( ion=1; ion<=LIMELM; ion++ )
                {
                        /* Interpolate for all tabulated photon energies at this temperature */
                        ret = LinterpTable(GauntFF[ion], TeGFF, N_PHOTON_GFF, N_TE_GFF, (realnum)phycon.alogte, GauntFF_T[ion], &ipTe);
                        if(ret == -1) 
                        {
                                fprintf(ioQQQ," LinterpTable for GffTable called with te out of bounds \n");
                                cdEXIT(EXIT_FAILURE);
                        }
                }

                /* Interpolate for all ions at required photon energies -- similar
                 * to LinterpTable, but not quite similar enough... */
                /* >>chng 04 jun 30, change nflux to nupper */
                ret = LinterpVector(GauntFF_T+lowion, PhoGFF, maxion-lowion+1, N_PHOTON_GFF,
                        rfield.anulog, rfield.nupper,/*rfield.nflux,*/ rfield.gff + lowion); 
                if(ret == -1) 
                {
                        fprintf(ioQQQ," LinterpVector for GffTable called with photon energy out of bounds \n");
                        cdEXIT(EXIT_FAILURE);
                }
        }
        else
        {
                /* this is flag that would have been set in gffsub, and
                 * printed in debug statement below.  We are not evaluating
                 * so set to -1 */
                if1 = -1;
                lgGauntF = false;
        }

        if( trace.lgTrace && trace.lgTrGant )
        {
                fprintf( ioQQQ, "     tfidle; gaunt factors?" );
                fprintf( ioQQQ, "%2c", TorF(lgGauntF) );

                fprintf( ioQQQ, "%2f g 1 2=%10.2e%9.2ld flag%2f guv(1,n)%10.2e\n", 
                  rfield.gff[1][0], rfield.gff[1][iso.ipIsoLevNIonCon[ipH_LIKE][ipHYDROGEN][2]-1],
                  if1, rfield.gff[1][iso.ipIsoLevNIonCon[ipH_LIKE][ipHYDROGEN][2]], 
                  rfield.gff[1][rfield.nflux-1] );
        }
        return;
}

/*tauff compute optical depth where cloud is thin to free-free and plasma freq */
STATIC void tauff(void)
{
        realnum fac;

        /* simply return if space not yet allocated */
        if( !lgOpacMalloced )
                return;

        DEBUG_ENTRY( "tauff()" );

        /* routine sets variable ipEnergyBremsThin, index for lowest cont cell that is optically thin */
        /* find frequency where continuum thin to free-free */
        while( rfield.ipEnergyBremsThin < rfield.nflux && 
                opac.TauAbsGeo[0][rfield.ipEnergyBremsThin] >= 1. )
        {
                ++rfield.ipEnergyBremsThin;
        }

        /* TFF will be frequency where cloud becomes optically thin to bremsstrahlung
         * >>chng 96 may 7, had been 2, change as per Kevin Volk bug report */
        if( rfield.ipEnergyBremsThin > 1 && opac.TauAbsGeo[0][rfield.ipEnergyBremsThin] > 0.001 )
        {
                /* tau can be zero when plasma frequency is within energy grid, */
                fac = (1.f - opac.TauAbsGeo[0][rfield.ipEnergyBremsThin-1])/(opac.TauAbsGeo[0][rfield.ipEnergyBremsThin] - 
                  opac.TauAbsGeo[0][rfield.ipEnergyBremsThin-1]);
                fac = MAX2(fac,0.f);
                rfield.EnergyBremsThin = rfield.anu[rfield.ipEnergyBremsThin-1] + rfield.widflx[rfield.ipEnergyBremsThin-1]*fac;
        }
        else
        {
                rfield.EnergyBremsThin = 0.f;
        }

        /* now evaluate the plasma frequency */
        rfield.plsfrq = (realnum)(2.729e-12*sqrt(dense.eden*1.2));

        if( rfield.ipPlasma > 0 )
        {
                /* >>chng 02 jul 25, increase index for plasma frequency until within proper cell */
                while( rfield.plsfrq > rfield.anu[rfield.ipPlasma]+rfield.widflx[rfield.ipPlasma]/2. )
                        ++rfield.ipPlasma;

                /* >>chng 02 jul 25, decrease index for plasma frequency until within proper cell */
                while( rfield.ipPlasma>2 && rfield.plsfrq < rfield.anu[rfield.ipPlasma]-rfield.widflx[rfield.ipPlasma]/2. )
                        --rfield.ipPlasma;
        }

        /* also remember the largest plasma frequency we encounter */
        rfield.plsfrqmax = MAX2(rfield.plsfrqmax, rfield.plsfrq);

        /* is plasma frequency within energy grid? */
        if( rfield.plsfrq > rfield.anu[0] )
        {
                rfield.lgPlasNu = true;
        }

        /* >>chng 96 jul 15, did not include plasma freq before
         * function returns larger of these two frequencies */
        rfield.EnergyBremsThin = MAX2(rfield.plsfrq,rfield.EnergyBremsThin);

        /* now increment ipEnergyBremsThin still further, until above plasma frequency */
        while( rfield.ipEnergyBremsThin < rfield.nflux && 
                rfield.anu[rfield.ipEnergyBremsThin] <= rfield.EnergyBremsThin )
        {
                ++rfield.ipEnergyBremsThin;
        }
        return;
}

/*velset set thermal velocities for all particles in gas */
STATIC void velset(void)
{
        long int nelem;
        double turb2;

        DEBUG_ENTRY( "velset()" );

        /* usually TurbVel =0, reset with turbulence command
         * cm/s here, but was entered in km/s with command */
        turb2 = POW2(DoppVel.TurbVel);

        /* this is option to dissipate the turbulence.  DispScale is entered with
         * dissipate keyword on turbulence command.  The velocity is reduced here,
         * by an assumed exponential scale, and also adds heat */
        if( DoppVel.DispScale > 0. )
        {
                /* square of exp depth dependence */
                turb2 *= sexp( 2.*radius.depth / DoppVel.DispScale );
        }

        /* in case of D-Critical flow include initial velocity as
         * a component of turbulence */
        if( wind.windv0 < 0. )
        {
                turb2 += POW2(wind.windv0);
        }

        /* computes one doppler width, in cm/sec,
         * for each element with atomic number the array index*/
        for( nelem=0; nelem < LIMELM; nelem++ )
        {
                DoppVel.doppler[nelem] = 
                        /*(realnum)sqrt(1.651e8*phycon.te/dense.AtomicWeight[nelem]+*/
                        /* >>chng 00 may 02 to physical constants */
                        (realnum)sqrt(2.*BOLTZMANN/ATOMIC_MASS_UNIT*phycon.te/dense.AtomicWeight[nelem]+
                  turb2);
                /* this is average (NOT rms) particle speed for Maxwell distribution, Mihalas 70, 9-70 */
                DoppVel.AveVel[nelem] = sqrt(8.*BOLTZMANN/PI/ATOMIC_MASS_UNIT*phycon.te/dense.AtomicWeight[nelem]);
        }

        /* DoppVel.doppler[LIMELM] is CO, vector is dim LIMELM+1 */
        /* C12O16 */
        DoppVel.doppler[LIMELM] = 
                (realnum)sqrt(2.*BOLTZMANN/ATOMIC_MASS_UNIT*phycon.te/
                (dense.AtomicWeight[5]+dense.AtomicWeight[7]) + turb2);
        DoppVel.AveVel[LIMELM] = 
                sqrt(8.*BOLTZMANN/ATOMIC_MASS_UNIT*phycon.te/
                (dense.AtomicWeight[5]+dense.AtomicWeight[7]) + turb2);

        /* C13O16 */
        DoppVel.doppler[LIMELM+1] = 
                (realnum)sqrt(2.*BOLTZMANN/ATOMIC_MASS_UNIT*phycon.te/
                (dense.AtomicWeight[5]*13./12.+dense.AtomicWeight[7]) + turb2);
        DoppVel.AveVel[LIMELM+1] = 
                sqrt(8.*BOLTZMANN/ATOMIC_MASS_UNIT*phycon.te/
                (dense.AtomicWeight[5]*13./12.+dense.AtomicWeight[7]) + turb2);

        /* H2 */
        DoppVel.doppler[LIMELM+2] = 
                (realnum)sqrt(2.*BOLTZMANN/ATOMIC_MASS_UNIT*phycon.te/
                (2.*dense.AtomicWeight[0]) + turb2);
        DoppVel.AveVel[LIMELM+2] = 
                sqrt(8.*BOLTZMANN/ATOMIC_MASS_UNIT*phycon.te/
                (2.*dense.AtomicWeight[0]) + turb2);
        return;
}

STATIC void FillGFF( void )
{

        long i,i1,i2,i3,j,charge,GffMAGIC = 80321;
        double Temp, photon;
        bool lgEOL;

        DEBUG_ENTRY( "FillGFF()" );

#       define chLine_LENGTH 1000
        char chLine[chLine_LENGTH];

        FILE *ioDATA;

        for( i = 0; i < N_TE_GFF; i++ )
        {
                TeGFF[i] = 0.5f*i;
        }
        /* >>chng 06 feb 14, assert thrown at T == 1e10 K, Ryan Porter proposes this fix */
        TeGFF[N_TE_GFF-1] += 0.01f;

        for( i = 0; i< N_PHOTON_GFF; i++ )
        {
                PhoGFF[i] = 0.125f*i - 8.f;
        }

        GauntFF = (realnum***)MALLOC( sizeof(realnum**)*(unsigned)(LIMELM+2) );
        for( i = 1; i <= LIMELM; i++ )
        {
                GauntFF[i] = (realnum**)MALLOC( sizeof(realnum*)*(unsigned)N_PHOTON_GFF );
                for( j = 0; j < N_PHOTON_GFF; j++ )
                {
                        GauntFF[i][j] = (realnum*)MALLOC( sizeof(realnum)*(unsigned)N_TE_GFF );
                }
        }

        GauntFF_T = (realnum**)MALLOC( sizeof(realnum*)*(unsigned)(LIMELM+2) );
        for( i = 1; i <= LIMELM; i++ )
        {
                GauntFF_T[i] = (realnum*)MALLOC( sizeof(realnum)*(unsigned)N_PHOTON_GFF );
        }

        if( !rfield.lgCompileGauntFF )
        {
                if( trace.lgTrace )
                        fprintf( ioQQQ," FillGFF opening gauntff.dat:");

                try
                {
                        ioDATA = open_data( "gauntff.dat", "r" );
                }
                catch( cloudy_exit )
                {
                        fprintf( ioQQQ, " Defaulting to on-the-fly computation, ");
                        fprintf( ioQQQ, "but the code runs much faster if you compile gauntff.dat!\n");
                        ioDATA = NULL;
                }

                if( ioDATA == NULL )
                {
                        /* Do on the fly computation of Gff's instead.  */
                        for( charge=1; charge<=LIMELM; charge++ )
                        {
                                for( i=0; i<N_PHOTON_GFF; i++ )
                                {
                                        photon = pow((realnum)10.f,PhoGFF[i]);
                                        for(j=0; j<N_TE_GFF; j++)
                                        {
                                                Temp = pow((realnum)10.f,TeGFF[j]);
                                                GauntFF[charge][i][j] = (realnum)cont_gaunt_calc( Temp, (double)charge, photon );
                                        }
                                }
                        }
                }
                else 
                {
                        /* check that magic number is ok */
                        if( read_whole_line( chLine , (int)sizeof(chLine) , ioDATA ) == NULL )
                        {
                                fprintf( ioQQQ, " FillGFF could not read first line of gauntff.dat.\n");
                                cdEXIT(EXIT_FAILURE);
                        }
                        i = 1;
                        i1 = (long)FFmtRead(chLine,&i,INPUT_LINE_LENGTH,&lgEOL);
                        i2 = (long)FFmtRead(chLine,&i,INPUT_LINE_LENGTH,&lgEOL);
                        i3 = (long)FFmtRead(chLine,&i,INPUT_LINE_LENGTH,&lgEOL);

                        if( i1 !=GffMAGIC || i2 !=N_PHOTON_GFF || i3 !=N_TE_GFF )
                        {
                                fprintf( ioQQQ, 
                                        " FillGFF: the version of gauntff.dat is not the current version.\n" );
                                fprintf( ioQQQ, 
                                        " FillGFF: I expected to find the numbers  %li %li %li and got %li %li %li instead.\n" ,
                                        GffMAGIC ,
                                        N_PHOTON_GFF,
                                        N_TE_GFF,
                                        i1 , i2 , i3 );
                                fprintf( ioQQQ, "Here is the line image:\n==%s==\n", chLine );
                                fprintf( ioQQQ, 
                                        " FillGFF: please recompile the data file with the COMPILE GAUNT command.\n" );
                                cdEXIT(EXIT_FAILURE);
                        }

                        /* now read in the data */
                        for( charge = 1; charge <= LIMELM; charge++ )
                        {
                                for( i = 0; i<N_PHOTON_GFF; i++ )
                                {
                                        /* get next line image */
                                        if( read_whole_line( chLine , (int)sizeof(chLine) , ioDATA ) == NULL )
                                        {
                                                fprintf( ioQQQ, " FillGFF could not read first line of gauntff.dat.\n");
                                                cdEXIT(EXIT_FAILURE);
                                        }
                                        /* each line starts with charge and energy level ( index in rfield ) */
                                        i3 = 1;
                                        i1 = (long)FFmtRead(chLine,&i3,INPUT_LINE_LENGTH,&lgEOL);
                                        i2 = (long)FFmtRead(chLine,&i3,INPUT_LINE_LENGTH,&lgEOL);
                                        /* check that these numbers are correct */
                                        if( i1!=charge || i2!=i )
                                        {
                                                fprintf( ioQQQ, " FillGFF detected insanity in gauntff.dat.\n");
                                                fprintf( ioQQQ, 
                                                        " FillGFF: please recompile the data file with the COMPILE GAUNT command.\n" );
                                                cdEXIT(EXIT_FAILURE);
                                        }

                                        /* loop over temperatures to produce array of free free gaunt factors   */
                                        for(j = 0; j < N_TE_GFF; j++)
                                        {
                                                GauntFF[charge][i][j] = (realnum)FFmtRead(chLine,&i3,chLine_LENGTH,&lgEOL);

                                                if( lgEOL )
                                                {
                                                        fprintf( ioQQQ, " FillGFF detected insanity in gauntff.dat.\n");
                                                        fprintf( ioQQQ, 
                                                                " FillGFF: please recompile the data file with the COMPILE GAUNT command.\n" );
                                                        cdEXIT(EXIT_FAILURE);
                                                }
                                        }
                                }

                        }

                        /* check that magic number is ok */
                        if( read_whole_line( chLine , (int)sizeof(chLine) , ioDATA ) == NULL )
                        {
                                fprintf( ioQQQ, " FillGFF could not read first line of gauntff.dat.\n");
                                cdEXIT(EXIT_FAILURE);
                        }
                        i = 1;
                        i1 = (long)FFmtRead(chLine,&i,INPUT_LINE_LENGTH,&lgEOL);
                        i2 = (long)FFmtRead(chLine,&i,INPUT_LINE_LENGTH,&lgEOL);
                        i3 = (long)FFmtRead(chLine,&i,INPUT_LINE_LENGTH,&lgEOL);

                        if( i1 !=GffMAGIC || i2 !=N_PHOTON_GFF || i3 !=N_TE_GFF )
                        {
                                fprintf( ioQQQ, 
                                        " FillGFF: the version of gauntff.dat is not the current version.\n" );
                                fprintf( ioQQQ, 
                                        " FillGFF: I expected to find the numbers  %li %li %li and got %li %li %li instead.\n" ,
                                        GffMAGIC ,
                                        N_PHOTON_GFF,
                                        N_TE_GFF,
                                        i1 , i2 , i3 );
                                fprintf( ioQQQ, "Here is the line image:\n==%s==\n", chLine );
                                fprintf( ioQQQ, 
                                        " FillGFF: please recompile the data file with the COMPILE GAUNT command.\n" );
                                cdEXIT(EXIT_FAILURE);
                        }

                        /* close the data file */
                        fclose( ioDATA );
                }
                if( trace.lgTrace )
                        fprintf( ioQQQ,"  - opened and read ok.\n");
        }
        else
        {
                /* option to create table of gaunt factors,
                 * executed with the compile gaunt command */
                FILE *ioGFF;

                /*GffMAGIC the magic number for the table of recombination coefficients */
                ioGFF = open_data( "gauntff.dat" , "w", AS_LOCAL_ONLY );
                fprintf(ioGFF,"%li\t%li\t%li\tGFF free-free gaunt factors, created by COMPILE GAUNT command, with %li energy levels and %li temperatures.\n",
                        GffMAGIC ,
                        N_PHOTON_GFF,
                        N_TE_GFF,
                        N_PHOTON_GFF,
                        N_TE_GFF );

                for( charge = 1; charge <= LIMELM; charge++ )
                {
                        for( i=0; i < N_PHOTON_GFF; i++ )
                        {
                                fprintf(ioGFF, "%li\t%li", charge, i );
                                /* loop over temperatures to produce array of gaunt factors     */
                                for(j = 0; j < N_TE_GFF; j++)
                                {
                                        /* Store gaunt factor in N_TE_GFF half dec steps */
                                        Temp = pow((realnum)10.f,TeGFF[j]);
                                        photon = pow((realnum)10.f,PhoGFF[i]);
                                        GauntFF[charge][i][j] = (realnum)cont_gaunt_calc( Temp, (double)charge, photon );
                                        fprintf(ioGFF, "\t%f", GauntFF[charge][i][j] );
                                }
                                fprintf(ioGFF, "\n" );
                        }
                }

                /* end the file with the same information */
                fprintf(ioGFF,"%li\t%li\t%li\tGFF free-free gaunt factors, created by COMPILE GAUNT command, with %li energy levels and %li temperatures.\n",
                        GffMAGIC ,
                        N_PHOTON_GFF,
                        N_TE_GFF,
                        N_PHOTON_GFF,
                        N_TE_GFF );

                fclose( ioGFF );

                fprintf( ioQQQ, "FillGFF: compilation complete, gauntff.dat created.\n" );
        }

        lgGffNotFilled = false;

        {
                /* We have already checked the validity of cont_gaunt_calc in sanitycheck.c.
                 * Now we check to see if the InterpolateGff routine also works correctly.      */
                /*@-redef@*/
                enum {DEBUG_LOC=false};
                /* if set true there will be two problems at very low temps */
                /*@+redef@*/
                if( DEBUG_LOC )
                {
                        double gaunt, error;
                        double tempsave = phycon.te;
                        long logu, loggamma2;

                        for( logu=-4; logu<=4; logu++)
                        {
                                /* Uncommenting each of the three print statements in this bit
                                 * will produce a nice table comparable to Table 2 of
                                 * >>refer      free-free       gaunts  Sutherland, R.S., 1998, MNRAS, 300, 321-330 */
                                /* fprintf(ioQQQ,"%li\t", logu);*/
                                for(loggamma2=-4; loggamma2<=4; loggamma2++)
                                { 
                                        double SutherlandGff[9][9]=
                                        {       {5.5243, 5.5213, 5.4983, 5.3780, 5.0090, 4.4354, 3.8317, 3.2472, 2.7008},
                                                {4.2581, 4.2577, 4.2403, 4.1307, 3.7816, 3.2436, 2.7008, 2.2126, 1.8041},
                                                {3.0048, 3.0125, 3.0152, 2.9434, 2.6560, 2.2131, 1.8071, 1.4933, 1.2771},
                                                {1.8153, 1.8367, 1.8880, 1.9243, 1.7825, 1.5088, 1.2886, 1.1507, 1.0747},
                                                {0.8531, 0.8815, 0.9698, 1.1699, 1.2939, 1.1988, 1.1033, 1.0501, 1.0237},
                                                {0.3101, 0.3283, 0.3900, 0.5894, 0.9725, 1.1284, 1.0825, 1.0419, 1.0202},
                                                {0.1007, 0.1080, 0.1335, 0.2281, 0.5171, 0.9561, 1.1065, 1.0693, 1.0355},
                                                {0.0320, 0.0344, 0.0432, 0.0772, 0.1997, 0.5146, 0.9548, 1.1042, 1.0680},
                                                {0.0101, 0.0109, 0.0138, 0.0249, 0.0675, 0.1987, 0.5146, 0.9547, 1.1040}};

                                        phycon.te = (TE1RYD/pow(10.,(double)loggamma2));
                                        phycon.alogte = log10(phycon.te);
                                        gaunt = InterpolateGff( 1, pow(10.,(double)(logu-loggamma2)) );
                                        error = fabs( gaunt - SutherlandGff[logu+4][loggamma2+4] ) /gaunt;
                                        /*fprintf(ioQQQ,"%1.3f\t", gaunt);*/
                                        if( error>0.05 )
                                        {
                                                fprintf(ioQQQ," tfidle found insane gff. log(u) %li, log(gamma2) %li, error %.3e\n",
                                                        logu, loggamma2, error );
                                        }
                                }
                                /*fprintf(ioQQQ,"\n");*/
                        }
                        phycon.te = tempsave;
                        phycon.alogte = log10(phycon.te);
                }
        }

        return;
}

/* Interpolate Gff at some temperature */
STATIC realnum InterpolateGff( long charge , double ERyd )
{
        double GauntAtLowerPho, GauntAtUpperPho;
        static long int ipTe=-1, ipPho=-1;
        double gaunt = 0.;
        double xmin , xmax;
        long i;

        DEBUG_ENTRY( "InterpolateGff()" );

        if( ipTe < 0 )
        {
                /* te totally unknown */
                if( phycon.alogte < TeGFF[0] || phycon.alogte > TeGFF[N_TE_GFF-1] )
                {
                        fprintf(ioQQQ," InterpolateGff called with te out of bounds \n");
                        cdEXIT(EXIT_FAILURE);
                }
                /* now search for temperature */
                for( i=0; i<N_TE_GFF-1; ++i )
                {
                        if( phycon.alogte > TeGFF[i] && phycon.alogte <= TeGFF[i+1] )
                        {
                                /* found the temperature - use it */
                                ipTe = i;
                                break;
                        }
                }
                ASSERT( (ipTe >=0) && (ipTe < N_TE_GFF-1)  );

        }
        else if( phycon.alogte < TeGFF[ipTe] )
        {
                /* temp is too low, must also lower ipTe */
                ASSERT( phycon.alogte > TeGFF[0] );
                /* decrement ipTe until it is correct */
                while( phycon.alogte < TeGFF[ipTe] && ipTe > 0)
                        --ipTe;
        }
        else if( phycon.alogte > TeGFF[ipTe+1] )
        {
                /* temp is too high */
                ASSERT( phycon.alogte <= TeGFF[N_TE_GFF-1] );
                /* increment ipTe until it is correct */
                while( phycon.alogte > TeGFF[ipTe+1] && ipTe < N_TE_GFF-1)
                        ++ipTe;
        }

        ASSERT( (ipTe >=0) && (ipTe < N_TE_GFF-1)  );

        /* ipTe should now be valid */
        ASSERT( phycon.alogte >= TeGFF[ipTe] && phycon.alogte <= TeGFF[ipTe+1] && ipTe < N_TE_GFF-1 );

        /***************/
        /* This bit is completely analogous to the above, but for the photon vector instead of temp.    */
        if( ipPho < 0 )
        {
                if( log10(ERyd) < PhoGFF[0] || log10(ERyd) > PhoGFF[N_PHOTON_GFF-1] )
                {
                        fprintf(ioQQQ," InterpolateGff called with photon energy out of bounds \n");
                        cdEXIT(EXIT_FAILURE);
                }
                for( i=0; i<N_PHOTON_GFF-1; ++i )
                {
                        if( log10(ERyd) > PhoGFF[i] && log10(ERyd) <= PhoGFF[i+1] )
                        {
                                ipPho = i;
                                break;
                        }
                }
                ASSERT( (ipPho >=0) && (ipPho < N_PHOTON_GFF-1)  );

        }
        else if( log10(ERyd) < PhoGFF[ipPho] )
        {
                ASSERT( log10(ERyd) >= PhoGFF[0] );
                while( log10(ERyd) < PhoGFF[ipPho] && ipPho > 0)
                        --ipPho;
        }
        else if( log10(ERyd) > PhoGFF[ipPho+1] )
        {
                ASSERT( log10(ERyd) <= PhoGFF[N_PHOTON_GFF-1] );
                while( log10(ERyd) > PhoGFF[ipPho+1] && ipPho < N_PHOTON_GFF-1)
                        ++ipPho;
        }
        ASSERT( (ipPho >=0) && (ipPho < N_PHOTON_GFF-1)  );
        ASSERT( log10(ERyd)>=PhoGFF[ipPho] 
                && log10(ERyd)<=PhoGFF[ipPho+1] && ipPho<N_PHOTON_GFF-1 );

        /* Calculate the answer...must interpolate on two variables.
         * First interpolate on T, at both the lower and upper photon energies.
         * Then interpolate between these results for the right photon energy.  */

        GauntAtLowerPho = (phycon.alogte - TeGFF[ipTe]) / (TeGFF[ipTe+1] - TeGFF[ipTe]) *
                (GauntFF[charge][ipPho][ipTe+1] - GauntFF[charge][ipPho][ipTe]) + GauntFF[charge][ipPho][ipTe];

        GauntAtUpperPho = (phycon.alogte - TeGFF[ipTe]) / (TeGFF[ipTe+1] - TeGFF[ipTe]) *
                (GauntFF[charge][ipPho+1][ipTe+1] - GauntFF[charge][ipPho+1][ipTe]) + GauntFF[charge][ipPho+1][ipTe];

        gaunt = (log10(ERyd) - PhoGFF[ipPho]) / (PhoGFF[ipPho+1] - PhoGFF[ipPho]) * 
                (GauntAtUpperPho - GauntAtLowerPho) + GauntAtLowerPho;

        xmax = MAX4( GauntFF[charge][ipPho][ipTe+1], GauntFF[charge][ipPho+1][ipTe+1],
                GauntFF[charge][ipPho][ipTe], GauntFF[charge][ipPho+1][ipTe] );
        ASSERT( gaunt <= xmax );

        xmin = MIN4( GauntFF[charge][ipPho][ipTe+1], GauntFF[charge][ipPho+1][ipTe+1],
                GauntFF[charge][ipPho][ipTe], GauntFF[charge][ipPho+1][ipTe] );
        ASSERT( gaunt >= xmin );

        ASSERT( gaunt > 0. );

        return (realnum)gaunt;
}

/* Interpolate in table t[lta][ltb], with physical values for the
         second index given by v[ltb], for values x, and put results in
         a[lta]; store the index found if that's useful; assumes v[] is
         sorted */
STATIC int LinterpTable(realnum **t, realnum *v, long int lta, long int ltb, realnum x, realnum *a, long int *pipx)
{
        long int ipx=-1;
        realnum frac;
        long i;

        DEBUG_ENTRY( "LinterpTable()" );

        if(pipx != NULL)
                ipx = *pipx;

        fhunt (v,ltb,x,&ipx);           /* search for index */
        if(pipx != NULL)
                *pipx = ipx;

        if( ipx == -1 || ipx == ltb )
        {
                return -1;
        }

        ASSERT( (ipx >=0) && (ipx < ltb-1)  );
        ASSERT( x >= v[ipx] && x <= v[ipx+1]);

        frac = (x - v[ipx]) / (v[ipx+1] - v[ipx]);
        for( i=0; i<lta; i++ )
        {
                a[i] = frac*t[i][ipx+1]+(1.f-frac)*t[i][ipx];
        }

        return 0;
}

/* Interpolate in table t[lta][ltb], with physical values for the second index given by v[ltb],
         for values yy[ny], and put results in a[lta][ly] */
STATIC int LinterpVector(realnum **t, realnum *v, long lta , long ltb, realnum *yy, long ly, realnum **a)
{
        realnum yl, frac;
        long i, j, n;

        DEBUG_ENTRY( "LinterpVector()" );

        if( yy[0] < v[0] || yy[ly-1] > v[ltb-1] )
        {
                return -1;
        }

        n = 0;
        yl = yy[n];
        for(j = 1; j < ltb && n < ly; j++) {
                while (yl < v[j] && n < ly) {
                        frac = (yl-v[j-1])/(v[j]-v[j-1]);
                        for(i = 0; i < lta; i++)
                                a[i][n] = frac*t[i][j]+(1.f-frac)*t[i][j-1];
                        n++;
                        if(n == ly)
                                break;
                        ASSERT( yy[n] >= yy[n-1] );
                        yl = yy[n];
                }
        }

        return 0;
}
STATIC void fhunt(realnum *xx, long int n, realnum x, long int *j)
{
        /*lint -e731 boolean argument to equal / not equal */
        long int jl, jm, jh, in;
        int up;

        jl = *j;
        up = (xx[n-1] > xx[0]);
        if(jl < 0 || jl >= n) 
        {
                jl = -1;
                jh = n;
        } 
        else 
        {
                in = 1;
                if((x >= xx[jl]) == up) 
                {
                        if(jl == n-1) 
                        {
                                *j = jl;
                                return;
                        }
                        jh = jl + 1;
                        while ((x >= xx[jh]) == up)
                        {
                                jl = jh;
                                in += in;
                                jh += in;
                                if(jh >= n)
                                {
                                        jh = n;
                                        break;
                                }
                        }
                }
                else
                {
                        if(jl == 0)
                        {
                                *j = -1;
                                return;
                        }
                        jh = jl--;
                        while ((x < xx[jl]) == up)
                        {
                                jh = jl;
                                in += in;
                                jl -= in;
                                if(jl <= 0)
                                {
                                        jl = 0;
                                        break;
                                }
                        }
                }
        }
        while (jh-jl != 1)
        {
                jm = (jh+jl)/2;
                if((x > xx[jm]) == up)
                        jl = jm;
                else
                        jh = jm;
        }
        *j = jl;
        return;
}
        /*lint +e731 boolean argument to equal / not equal */

---