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/****************************************************************************/
/* IO.C: I/O routines for export version of hierarchical N-body code. */
/* Public routines: inputdata(), initoutput(), stopoutput(), output(). */
/* */
/* Copyright (c) 1993 by Joshua E. Barnes, Honolulu, HI. */
/* It's free because it's yours. */
/****************************************************************************/
#include "code.h"
local void diagnostics(void);
local void in_int(stream, int *);
local void in_real(stream, real *);
local void in_vector(stream, vector);
local void out_int(stream, int);
local void out_real(stream, real);
local void out_vector(stream, vector);
local void printvec(string, vector);
/*
* INPUTDATA: read initial conditions from input file.
*/
void inputdata(void)
{
stream instr;
permanent char headbuf[128];
int ndim;
bodyptr p;
instr = fopen(infile, "r"); /* open input stream */
if (instr == NULL)
error("inputdata: cannot find file %s\n", infile);
sprintf(headbuf, "Hierarchical code: input file %s", infile);
headline = headbuf;
in_int(instr, &nbody);
if (nbody < 1)
error("inputdata: nbody = %d is absurd\n", nbody);
in_int(instr, &ndim);
if (ndim != NDIM)
error("inputdata: ndim = %d is absurd\n", ndim);
in_real(instr, &tnow);
bodytab = (bodyptr) allocate(nbody * sizeof(body));
for (p = bodytab; p < bodytab+nbody; p++) /* loop over new bodies */
Type(p) = BODY; /* init body type */
for (p = bodytab; p < bodytab+nbody; p++)
in_real(instr, &Mass(p));
for (p = bodytab; p < bodytab+nbody; p++)
in_vector(instr, Pos(p));
for (p = bodytab; p < bodytab+nbody; p++)
in_vector(instr, Vel(p));
fclose(instr); /* close input stream */
}
/*
* INITOUTPUT: initialize output routines.
*/
local stream outstr; /* output stream pointer */
void initoutput(void)
{
printf("\n%s\n\n", headline); /* print headline, params */
printf("%10s%10s%10s%10s%10s%10s%10s\n", "nbody", "dtime", "eps",
"theta", "usequad", "dtout", "tstop");
printf("%10d%10.5f%10.4f%10.2f%10s%10.4f%10.4f\n\n", nbody, 1/freq, eps,
theta, usequad ? "true" : "false", 1/freqout, tstop);
if (*options != NULLCHR) /* print options, if any */
printf("\tOptions: %s\n\n", options);
printf("\n");
if (*outfile != NULLCHR) { /* output file specified? */
outstr = fopen(outfile, "w"); /* setup output stream */
if (outstr == NULL)
error("initoutput: cannot open file %s\n", outfile);
} else
outstr = NULL; /* turn off data output */
}
/*
* STOPOUTPUT: finish up after a run.
*/
void stopoutput(void)
{
if (outstr != NULL)
fclose(outstr);
}
/*
* Counters and accumulators for output routines.
*/
local real mtot; /* total mass of N-body system */
local real etot[3]; /* binding, kinetic, potential energy */
local matrix keten; /* kinetic energy tensor */
local matrix peten; /* potential energy tensor */
local vector cmphase[2]; /* center of mass coordinates */
local vector amvec; /* angular momentum vector */
/*
* OUTPUT: compute diagnostics and output data.
*/
void output(void)
{
int nttot, nbavg, ncavg;
bodyptr p;
diagnostics(); /* compute std diagnostics */
nttot = n2bcalc + nbccalc;
nbavg = (int) ((real) n2bcalc / (real) nbody);
ncavg = (int) ((real) nbccalc / (real) nbody);
printf("%10s%10s%10s%10s%10s%10s%10s\n", "tnow", "T+U",
"T/U", "nttot", "nbavg", "ncavg", "cputime");
printf("%10.3f%10.4f%10.4f%10d%10d%10d%10.2f\n\n", tnow, etot[0],
etot[1]/etot[2], nttot, nbavg, ncavg, cputime());
if (scanopt(options, "tree-report")) { /* report on tree structure */
printf("\t %20s%20s%20s\n", "rsize", "cellused", "maxlevel");
printf("\t %20.2f%20d%20d\n\n", rsize, cellused, maxlevel);
}
printvec("cm pos", cmphase[0]);
printvec("cm vel", cmphase[1]);
printvec("am vec", amvec);
printf("\n");
if (outstr != NULL && /* output stream open and */
(tout - 0.01 / freq) <= tnow) { /* ...time for next output? */
out_int(outstr, nbody); /* write particle data */
out_int(outstr, NDIM);
out_real(outstr, tnow);
for (p = bodytab; p < bodytab+nbody; p++)
out_real(outstr, Mass(p));
for (p = bodytab; p < bodytab+nbody; p++)
out_vector(outstr, Pos(p));
for (p = bodytab; p < bodytab+nbody; p++)
out_vector(outstr, Vel(p));
fflush(outstr); /* drain output buffer */
printf("\tParticle data written to file %s\n\n", outfile);
tout += 1 / freqout; /* schedule next data out */
}
}
/*
* DIAGNOSTICS: compute various dynamical diagnostics.
*/
local void diagnostics(void)
{
register bodyptr p;
real velsq;
vector tmpv;
matrix tmpt;
mtot = 0.0; /* zero total mass */
etot[1] = etot[2] = 0.0; /* zero total KE and PE */
CLRM(keten); /* zero ke tensor */
CLRM(peten); /* zero pe tensor */
CLRV(cmphase[0]); /* zero c. of m. position */
CLRV(cmphase[1]); /* zero c. of m. velocity */
CLRV(amvec); /* zero am vector */
for (p = bodytab; p < bodytab+nbody; p++) { /* loop over all particles */
mtot += Mass(p); /* sum particle masses */
DOTVP(velsq, Vel(p), Vel(p)); /* square vel vector */
etot[1] += 0.5 * Mass(p) * velsq; /* sum current KE */
etot[2] += 0.5 * Mass(p) * Phi(p); /* and current PE */
MULVS(tmpv, Vel(p), 0.5 * Mass(p)); /* sum 0.5 m v_i v_j */
OUTVP(tmpt, tmpv, Vel(p));
ADDM(keten, keten, tmpt);
MULVS(tmpv, Pos(p), Mass(p)); /* sum m r_i a_j */
OUTVP(tmpt, tmpv, Acc(p));
ADDM(peten, peten, tmpt);
MULVS(tmpv, Pos(p), Mass(p)); /* sum cm position */
ADDV(cmphase[0], cmphase[0], tmpv);
MULVS(tmpv, Vel(p), Mass(p)); /* sum cm momentum */
ADDV(cmphase[1], cmphase[1], tmpv);
CROSSVP(tmpv, Pos(p), Vel(p)); /* sum angular momentum */
MULVS(tmpv, tmpv, Mass(p));
ADDV(amvec, amvec, tmpv);
}
etot[0] = etot[1] + etot[2]; /* sum KE and PE */
DIVVS(cmphase[0], cmphase[0], mtot); /* normalize cm coords */
DIVVS(cmphase[1], cmphase[1], mtot);
}
/*
* Low-level input and output operations.
*/
local void in_int(stream str, int *iptr)
{
#ifdef CCURED
if((resetScanfCount(),
*iptr = ccured_fscanf_int(str, "%d"),
getScanfCount()) != 1)
error("in_int: input conversion error\n");
#else
if (fscanf(str, "%d", iptr) != 1)
error("in_int: input conversion error\n");
#endif
}
local void in_real(stream str, real *rptr)
{
double tmp;
#ifdef CCURED
if((resetScanfCount(),
tmp = ccured_fscanf_double(str, "%lf"),
getScanfCount()) != 1)
#else
if (fscanf(str, "%lf", &tmp) != 1)
#endif
error("in_real: input conversion error\n");
*rptr = tmp;
}
local void in_vector(stream str, vector vec)
{
double tmpx, tmpy, tmpz;
#ifdef CCURED
if((resetScanfCount(),
tmpx = ccured_fscanf_double(str, "%lf"),
tmpx = ccured_fscanf_double(str, "%lf"),
tmpx = ccured_fscanf_double(str, "%lf"),
getScanfCount()) != 3)
#else
if (fscanf(str, "%lf%lf%lf", &tmpx, &tmpy, &tmpz) != 3)
#endif
error("in_vector: input conversion error\n");
vec[0] = tmpx; vec[1] = tmpy; vec[2] = tmpz;
}
local void out_int(stream str, int ival)
{
fprintf(str, " %d\n", ival);
}
local void out_real(stream str, real rval)
{
fprintf(str, " %21.14E\n", rval);
}
local void out_vector(stream str, vector vec)
{
fprintf(str, " %21.14E %21.14E %21.14E\n", vec[0], vec[1], vec[2]);
}
local void printvec(string name, vector vec)
{
printf(" %10s%10.4f%10.4f%10.4f\n",
name, vec[0], vec[1], vec[2]);
}
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