Exemplo n.º 1
0
/*------------------------------------------------------------------------------
  Determine whether the first vertex in vert
  is closer to the nearest vertex or to the nearest antivertex of poly.

  Return value: 0 or 1 as first vertex of vert is closer to the nearest
		       vertex or antivertex of poly;
		-1 if error.
*/
int antivert(vertices *vert, polygon *poly)
{
    const int do_vcirc = 0, nve = 1, per = 0;
    int anti, ier, iv, nev, nev0, nv;
    int *ipv, *gp, *ev;
    double cm, cmmax, cmmin, tol;
    double *angle;
    vec rp;
    vec *ve;

    /* vert has no vertices */
    if (vert->nv == 0) return(0);

    /* vertices of polygon */
    tol = mtol;
    ier = gverts(poly, do_vcirc, &tol, per, nve, &nv, &ve, &angle, &ipv, &gp, &nev, &nev0, &ev);

    /* error */
    if (ier) return(-1);

    /* poly has less than 3 vertices */
    if (nv < 3) return(0);

    /* convert first vertex to unit vector */
    azel_to_rp(&vert->v[0], rp);

    cmmin = 2.;
    cmmax = 0.;
    for (iv = 0; iv < nv; iv++) {
	cm = cmij(rp, ve[iv]);
	if (cm < cmmin) cmmin = cm;
	if (cm > cmmax) cmmax = cm;
    }
    anti = ((cmmin + cmmax <= 2.)? 0 : 1);

    return(anti);
}
Exemplo n.º 2
0
/*------------------------------------------------------------------------------
  Angles within mask along circles centred at az el, radii th.

  Anglar positions az, el are read from azel_in_filename,
  angular radii th are read from th_in_filename,
  or from azel_in_filename if th_in_filename is null,
  and the results are written to out_filename.

  Implemented as interpretive read/write, to permit interactive behaviour.

   Input: azel_in_filename = name of file to read az, el from;
			"" or "-" means read from standard input.
	  th_in_filename = name of file to read th from;
			null means read from azel_in_filename;
			"-" means read from standard input.
	  out_filename = name of file to write to;
			"" or "-" means write to standard output.
	  fmt = pointer to format structure.
	  npoly = number of polygons in poly array.
	  poly = array of pointers to polygons.
  Return value: number of lines written,
		or -1 if error occurred.
*/
int drangle(char *azel_in_filename, char *th_in_filename, char *out_filename, format *fmt, int npoly, polygon *poly[/*npoly*/])
{
#define AZEL_STR_LEN	32
    char input[] = "input", output[] = "output";
    /* maximum number of angular angular radii: will expand as necessary */
    static int nthmax = 0;
    static int ndrmax = 0;
    static long double *th = 0x0, *cm = 0x0, *drsum = 0x0;
    static long double *dr = 0x0;

#ifdef TIME
    clock_t time;
#endif
    char inunit, outunit;
    char *word, *next;
    char az_str[AZEL_STR_LEN], el_str[AZEL_STR_LEN], th_str[AZEL_STR_LEN], dr_str[AZEL_STR_LEN];
    int ier, ird, ith, len, lenth, np, nt, nth;
    long double rp[3], s, t;
    azel v;
    char *out_fn;
    FILE *outfile;

    inunit = (fmt->inunit == 'h')? 'd' : fmt->inunit;

    /* read angular radii from th_in_filename */
    if (th_in_filename) {

	/* open th_in_filename for reading */
	if (strcmp(th_in_filename, "-") == 0) {
	    file.file = stdin;
	    file.name = input;
	} else {
	    file.file = fopen(th_in_filename, "r");
	    if (!file.file) {
		fprintf(stderr, "cannot open %s for reading\n", th_in_filename);
		return(-1);
	    }
	    file.name = th_in_filename;
	}
	file.line_number = 0;

	msg("will take units of input th angles in %s to be ", file.name);
	switch (inunit) {
#include "angunit.h"
	}
	msg("\n");

	/* read angular radii from th_in_filename */
	nth = 0;
	while (1) {
	    /* read line */
	    ird = rdline(&file);
	    /* serious error */
	    if (ird == -1) return(-1);
	    /* EOF */
	    if (ird == 0) break;
	    /* read angular radius from line */
	    ird = rdangle(file.line, &next, inunit, &t);
	    /* error */
	    if (ird < 1) {
		/* retry if nothing read, otherwise break */
		if (nth > 0) break;
	    /* ok */
	    } else if (ird == 1) {
		if (nth >= nthmax) {
		    if (nthmax == 0) {
			nthmax = 64;
		    } else {
			nthmax *= 2;
		    }
		    /* (re)allocate memory for th array */
		    th = (long double *) realloc(th, sizeof(long double) * nthmax);
		    if (!th) {
			fprintf(stderr, "drangle: failed to allocate memory for %d long doubles\n", nthmax);
			return(-1);
		    }
		}
		/* copy angular radius into th array */
		th[nth] = t;
		nth++;
	    }
	}

	if (file.file != stdin) {
	    /* close th_in_filename */
	    fclose(file.file);
	    /* advise */
	    msg("%d angular radii read from %s\n", nth, file.name);
	}

	if (nth == 0) return(nth);

	/* (re)allocate memory for th array */
	th = (long double *) realloc(th, sizeof(long double) * nth);
	if (!th) {
	    fprintf(stderr, "drangle: failed to allocate memory for %d long doubles\n", nth);
	    return(-1);
	}
	/* (re)allocate memory for cm array */
	cm = (long double *) realloc(cm, sizeof(long double) * nth);
	if (!cm) {
	    fprintf(stderr, "drangle: failed to allocate memory for %d long doubles\n", nth);
	    return(-1);
	}
	/* (re)allocate memory for drsum array */
	drsum = (long double *) realloc(drsum, sizeof(long double) * nth);
	if (!drsum) {
	    fprintf(stderr, "drangle: failed to allocate memory for %d long doubles\n", nth);
	    return(-1);
	}
	nthmax = nth;
    }

    /* open azel_in_filename for reading */
    if (!azel_in_filename || strcmp(azel_in_filename, "-") == 0) {
	file.file = stdin;
	file.name = input;
    } else {
	file.file = fopen(azel_in_filename, "r");
	if (!file.file) {
	    fprintf(stderr, "cannot open %s for reading\n", azel_in_filename);
	    return(-1);
	}
	file.name = azel_in_filename;
    }
    file.line_number = 0;

    /* open out_filename for writing */
    if (!out_filename || strcmp(out_filename, "-") == 0) {
	outfile = stdout;
	out_fn = output;
    } else {
	outfile = fopen(out_filename, "w");
	if (!outfile) {
	    fprintf(stderr, "cannot open %s for writing\n", out_filename);
	    return(-1);
	}
	out_fn = out_filename;
    }

    /* advise input angular units */
    if (th_in_filename) {
	msg("will take units of input az, el angles in %s to be ", file.name);
    } else {
	msg("will take units of input az, el, and th angles in %s to be ", file.name);
    }
    switch (fmt->inunit) {
#include "angunit.h"
    }
    if (!th_in_filename && fmt->inunit == 'h') {
	msg(", th in deg");
    }
    msg("\n");

    /* advise output angular unit */
    outunit = (fmt->outunit == 'h')? 'd' : fmt->outunit;
    msg("units of output DR angles will be ");
    switch (outunit) {
#include "angunit.h"
    }
    msg("\n");

#ifdef TIME
    printf("timing ... ");
    fflush(stdout);
    time = clock();
#endif

    /* length of az, el and th, dr strings to be written to output */
    t = 0.;
    wrangle(t, fmt->inunit, fmt->outprecision, AZEL_STR_LEN, az_str);
    len = strlen(az_str);
    t = 0.;
    wrangle(t, inunit, fmt->outprecision, AZEL_STR_LEN, th_str);
    lenth = strlen(th_str);

    /* write header */
    if (!summary) {
	if (fmt->inunit == 'h') {
	    sprintf(az_str, "az(hms)");
	    sprintf(el_str, "el(dms)");
	    sprintf(th_str, "th(d):");
	} else {
	    sprintf(az_str, "az(%c)", fmt->inunit);
	    sprintf(el_str, "el(%c)", fmt->inunit);
	    sprintf(th_str, "th(%c):", fmt->inunit);
	}
	if (th_in_filename) {
	    fprintf(outfile, "%*s %*s %*s\n", len, " ", len, " ", lenth, th_str);
	}
	fprintf(outfile, "%*s %*s", len, az_str, len, el_str);
	if (th_in_filename) {
	    for (ith = 0; ith < nth; ith++) {
		wrangle(th[ith], inunit, fmt->outprecision, AZEL_STR_LEN, th_str);
		fprintf(outfile, " %s", th_str);
	    }
	    fprintf(outfile, "\n");
	} else {
	    fprintf(outfile, " %*s\n", lenth, th_str);
	}
    }

    /* initialize th and drsum */
    if (th_in_filename) {
	/* convert th from input units to radians */
	for (ith = 0; ith < nth; ith++) {
	    scale(&th[ith], inunit, 'r');
	}

	/* initialize sum of dr to zero */
	for (ith = 0; ith < nth; ith++) {
	    drsum[ith] = 0.;
	}
    }

    /* interpretive read/write loop */
    np = 0;
    nt = 0;
    while (1) {
	/* read line */
	ird = rdline(&file);
	/* serious error */
	if (ird == -1) return(-1);
	/* EOF */
	if (ird == 0) break;

	/* read <az> */
	word = file.line;
	ird = rdangle(word, &next, fmt->inunit, &v.az);
	/* skip header */
	if (ird != 1 && np == 0) continue;
	/* otherwise exit on unrecognized characters */
	if (ird != 1) break;

	/* read <el> */
	word = next;
	ird = rdangle(word, &next, fmt->inunit, &v.el);
	/* skip header */
	if (ird != 1 && np == 0) continue;
	/* otherwise exit on unrecognized characters */
	if (ird != 1) break;

	/* convert az and el from input units to radians */
	scale_azel(&v, fmt->inunit, 'r');

	/* read th */
	if (!th_in_filename) {
	    nth = 0;
	    while (1) {
		word = next;
		ird = rdangle(word, &next, inunit, &t);
		/* done */
		if (ird < 1) break;
		/* ok */
		if (nth >= nthmax) {
		    if (nthmax == 0) {
			nthmax = 64;
		    } else {
			nthmax *= 2;
		    }
		    th = (long double *) realloc(th, sizeof(long double) * nthmax);
		    if (!th) {
			fprintf(stderr, "drangle: failed to allocate memory for %d long doubles\n", nthmax);
			return(-1);
		    }
		    /* (re)allocate memory for cm array */
		    cm = (long double *) realloc(cm, sizeof(long double) * nthmax);
		    if (!cm) {
			fprintf(stderr, "drangle: failed to allocate memory for %d long doubles\n", nthmax);
			return(-1);
		    }
		}
		th[nth] = t;
		/* increment count of angular radii */
		nth++;
	    }
	    /* convert th from input units to radians */
	    for (ith = 0; ith < nth; ith++) {
		scale(&th[nth], inunit, 'r');
	    }
	}

	/* allocate memory for dr */
	if (nth > ndrmax) {
	    ndrmax = nth;
	    dr = (long double *) realloc(dr, sizeof(long double) * ndrmax);
	    if (!dr) {
		fprintf(stderr, "drangle: failed to allocate memory for %d long doubles\n", ndrmax);
		return(-1);
	    }
	}

	/* unit vector corresponding to angular position az, el */
	azel_to_rp(&v, rp);

	/* limiting cm = 1-cosl(th) values to each polygon */
	ier = cmlim_polys(npoly, poly, mtol, rp);
	if (ier == -1) return(-1);

	/* cm = 1 - cosl(th) */
	for (ith = 0; ith < nth; ith++) {
	    s = sinl(th[ith] / 2.);
	    cm[ith] = 2. * s * s;
	}

	/* angles about rp direction at radii th */
	ier = drangle_polys(npoly, poly, mtol, rp, nth, cm, dr);
	if (ier == -1) return(-1);

	/* sum of dr at radii th */
	if (th_in_filename) {
	    for (ith = 0; ith < nth; ith++) {
		drsum[ith] += dr[ith];
	    }
	}

	/* convert az and el from radians to original input units */
	scale_azel(&v, 'r', fmt->inunit);

	/* write result */
	if (!summary) {
	    wrangle(v.az, fmt->inunit, fmt->outprecision, AZEL_STR_LEN, az_str);
	    wrangle(v.el, fmt->inunit, fmt->outprecision, AZEL_STR_LEN, el_str);
	    fprintf(outfile, "%s %s", az_str, el_str);
	    for (ith = 0; ith < nth; ith++) {
		scale(&dr[ith], 'r', outunit);
		wrangle(dr[ith], outunit, fmt->outprecision, AZEL_STR_LEN, dr_str);
		fprintf(outfile, " %s", dr_str);
	    }
	    fprintf(outfile, "\n");
	    fflush(outfile);
	}

        /* increment counters of results */
	np++;
	nt += nth;

	/* warn about a potentially huge output file */
	if (np == 100 && !summary && th_in_filename && outfile != stdout) {
	    msg("hmm, looks like %s could grow pretty large ...\n", out_fn);
	    msg("try using the -h switch if you only want a summary in the output file\n");
	}
    }

    /* write sum of dr */
    if (summary) {
	sprintf(th_str, "th(%c)", inunit);
	sprintf(dr_str, "DR(%c)", outunit);
	fprintf(outfile, "%*s %*s\n", lenth, th_str, lenth, dr_str);
	for (ith = 0; ith < nth; ith++) {
	    scale(&th[ith], 'r', inunit);
	    wrangle(th[ith], inunit, fmt->outprecision, AZEL_STR_LEN, th_str);
	    scale(&drsum[ith], 'r', outunit);
	    wrangle(drsum[ith] / (long double)np, outunit, fmt->outprecision, AZEL_STR_LEN, dr_str);
	    fprintf(outfile, "%s %s\n", th_str, dr_str);
	}
	fflush(outfile);
    } else if (th_in_filename) {
	fprintf(outfile, "%*s", 2 * len + 1, "Average:");
	for (ith = 0; ith < nth; ith++) {
	    scale(&drsum[ith], 'r', outunit);
	    wrangle(drsum[ith] / (long double)np, outunit, fmt->outprecision, AZEL_STR_LEN, dr_str);
	    fprintf(outfile, " %s", dr_str);
	}
	fprintf(outfile, "\n");
	fflush(outfile);
    }

    /* close azel_in_filename */
    if (file.file != stdin) {
	fclose(file.file);
    }

#ifdef TIME
    time = clock() - time;
    printf("done in %Lg sec\n", (float)time / (float)CLOCKS_PER_SEC);
#endif

    /* advise */
    if (outfile != stdout) {
	fclose(outfile);
	if (summary) {
	    msg("drangle: header + %d lines written to %s\n", nth, out_fn);
	} else {
	    if (th_in_filename) {
		msg("drangle: %d x %d = ", nth, np);
	    } else {
		msg("drangle: total of ");
	    }
	    msg("%d angles at %d positions written to %s\n", nt, np, out_fn);
	}
    }

    return(nt);
}
Exemplo n.º 3
0
/*------------------------------------------------------------------------------
  Counts of pairs in bins bounded by radii th, centred at az el.

  Anglar positions az, el are read from azel_in_filename,
  angular radii th are read from th_in_filename,
  or from azel_in_filename if th_in_filename is null,
  and the results are written to out_filename.

  Implemented as interpretive read/write, to permit interactive behaviour.

   Input: azel_in_filename = name of file to read az, el from;
			"" or "-" means read from standard input.
	  th_in_filename = name of file to read th from;
			"" or "-" means read from standard input.
	  out_filename = name of file to write to;
			"" or "-" means write to standard output.
	  fmt = pointer to format structure.
	  npoly = number of polygons in poly array.
	  poly = array of pointers to polygons.
  Return value: number of distinct pairs counted,
		or -1 if error occurred.
*/
long ddcount(char *azel_in_filename, char *th_in_filename, char *out_filename, format *fmt, int npoly, polygon *poly[/*npoly*/])
{
#define AZEL_STR_LEN	32
    char input[] = "input", output[] = "output";
    /* maximum number of angular angular radii: will expand as necessary */
    static int nthmax = 0;
    /* maximum number of az-el points: will expand as necessary */
    static int nazelmax = 0;
    static int *dd = 0x0, *id = 0x0, *iord = 0x0;
    static long double *cm = 0x0, *th = 0x0;
    static azel *v = 0x0;
    static vec *rp = 0x0;

#ifdef TIME
    clock_t time;
#endif
    char inunit;
    char *word, *next;
    char th_str[AZEL_STR_LEN];
    int i, iazel, idi, ird, ith, j, jazel, manyid, nazel, nid, noid, nth;
    int *id_p;
    long np;
    long double az, cmm, el, s, t;
    char *out_fn;
    FILE *outfile;

    /* open th_in_filename for reading */
    if (strcmp(th_in_filename, "-") == 0) {
	file.file = stdin;
	file.name = input;
    } else {
	file.file = fopen(th_in_filename, "r");
	if (!file.file) {
	    fprintf(stderr, "cannot open %s for reading\n", th_in_filename);
	    return(-1);
	}
	file.name = th_in_filename;
    }
    file.line_number = 0;

    inunit = (fmt->inunit == 'h')? 'd' : fmt->inunit;
    msg("will take units of input th angles in %s to be ", file.name);
    switch (inunit) {
#include "angunit.h"
    }
    msg("\n");

    /* read angular radii th from th_in_filename */
    nth = 0;
    while (1) {
	/* read line */
	ird = rdline(&file);
	/* serious error */
	if (ird == -1) return(-1);
	/* EOF */
	if (ird == 0) break;
	/* read angular radius from line */
	ird = rdangle(file.line, &next, inunit, &t);
	/* error */
	if (ird < 1) {
	    /* retry if nothing read, otherwise break */
	    if (nth > 0) break;
	/* ok */
	} else if (ird == 1) {
	    if (nth >= nthmax) {
		if (nthmax == 0) {
		    nthmax = 64;
		} else {
		    nthmax *= 2;
		}
		/* (re)allocate memory for th array */
		th = (long double *) realloc(th, sizeof(long double) * nthmax);
		if (!th) {
		    fprintf(stderr, "ddcount: failed to allocate memory for %d long doubles\n", nthmax);
		    return(-1);
		}
	    }
	    /* store th */
	    th[nth] = t;
	    nth++;
	}
    }

    if (file.file != stdin) {
	/* close th_in_filename */
	fclose(file.file);
	/* advise */
	msg("%d angular radii read from %s\n", nth, file.name);
    }

    if (nth == 0) return(nth);

    /* open azel_in_filename for reading */
    if (!azel_in_filename || strcmp(azel_in_filename, "-") == 0) {
	file.file = stdin;
	file.name = input;
    } else {
	file.file = fopen(azel_in_filename, "r");
	if (!file.file) {
	    fprintf(stderr, "cannot open %s for reading\n", azel_in_filename);
	    return(-1);
	}
	file.name = azel_in_filename;
    }
    file.line_number = 0;

    /* advise input angular units */
    msg("will take units of input az, el angles in %s to be ", file.name);
    switch (fmt->inunit) {
#include "angunit.h"
    }
    msg("\n");

    /* read angular positions az, el from azel_in_filename */
    nazel = 0;
    while (1) {
	/* read line */
	ird = rdline(&file);
	/* serious error */
	if (ird == -1) return(-1);
	/* EOF */
	if (ird == 0) break;

	/* read <az> */
	word = file.line;
	ird = rdangle(word, &next, fmt->inunit, &az);
	/* skip header */
	if (ird != 1 && nazel == 0) continue;
	/* otherwise exit on unrecognized characters */
	if (ird != 1) break;

	/* read <el> */
	word = next;
	ird = rdangle(word, &next, fmt->inunit, &el);
	/* skip header */
	if (ird != 1 && nazel == 0) continue;
	/* otherwise exit on unrecognized characters */
	if (ird != 1) break;

	/* (re)allocate memory for array of az-el points */
	if (nazel >= nazelmax) {
	    if (nazelmax == 0) {
		nazelmax = 64;
	    } else {
		nazelmax *= 2;
	    }
	    v = (azel *) realloc(v, sizeof(azel) * nazelmax);
	    if (!v) {
		fprintf(stderr, "ddcount: failed to allocate memory for %d az-el points\n", nazelmax);
		return(-1);
	    }
	}

	/* record az-el */
	v[nazel].az = az;
	v[nazel].el = el;

        /* increment number of az-el points */
	nazel++;
    }

    if (file.file != stdin) {
	/* close azel_in_filename */
	fclose(file.file);
	/* advise */
	msg("%d angular positions az, el read from %s\n", nazel, file.name);
    }

    if (nazel == 0) return(nazel);

    /* open out_filename for writing */
    if (!out_filename || strcmp(out_filename, "-") == 0) {
	outfile = stdout;
	out_fn = output;
    } else {
	outfile = fopen(out_filename, "w");
	if (!outfile) {
	    fprintf(stderr, "cannot open %s for writing\n", out_filename);
	    return(-1);
	}
	out_fn = out_filename;
    }

    /* (re)allocate memory */
    cm = (long double *) realloc(dd, sizeof(long double) * nth);
    if (!cm) {
	fprintf(stderr, "ddcount: failed to allocate memory for %d long doubles\n", nth);
	return(-1);
    }
    dd = (int *) realloc(dd, sizeof(int) * nth);
    if (!dd) {
	fprintf(stderr, "ddcount: failed to allocate memory for %d ints\n", nth);
	return(-1);
    }
    id = (int *) realloc(id, sizeof(int) * nazel);
    if (!id) {
	fprintf(stderr, "ddcount: failed to allocate memory for %d ints\n", nazel);
	return(-1);
    }
    rp = (vec *) realloc(rp, sizeof(vec) * nazel);
    if (!rp) {
	fprintf(stderr, "ddcount: failed to allocate memory for %d unit vectors\n", nazel);
	return(-1);
    }
    iord = (int *) realloc(iord, sizeof(int) * nazel);
    if (!iord) {
	fprintf(stderr, "ddcount: failed to allocate memory for %d ints\n", nazel);
	return(-1);
    }

    /* store 1 - cosl(th) in cm array */
    for (ith = 0; ith < nth; ith++) {
	t = th[ith];
	scale(&t, inunit, 'r');
	s = sinl(t / 2.);
	cm[ith] = 2. * s * s;
    }

    /* convert az-el angles to radians */
    for (iazel = 0; iazel < nazel; iazel++) {
	scale_azel(&v[iazel], fmt->inunit, 'r');
    }

    /* convert az-el points to unit vectors */
    for (iazel = 0; iazel < nazel; iazel++) {
	azel_to_rp(&v[iazel], rp[iazel]);
    }

    /* polygon id number(s) of az-el points */
    msg("figuring polygon id number(s) of each az-el point ...");
    noid = 0;
    manyid = 0;
    for (iazel = 0; iazel < nazel; iazel++) {
	nid = poly_id(npoly, poly, v[iazel].az, v[iazel].el, &id_p);
	if (nid == 0) {
	    noid++;
	} else if (nid > 1) {
	    manyid++;
	}
	/* store first polygon id of point */
	if (nid == 0) {
	    id[iazel] = -1;
	} else {
	    id[iazel] = id_p[0];
	}
    }
    msg(" done\n");
    if (noid > 0) {
	msg("%d az-el points lie outside the angular mask: discard them\n", noid);
    }
    if (manyid > 0) {
	msg("%d az-el points lie inside more than one polygon: use only first polygon\n", manyid);
    }

    /* order az-el points in increasing order of polygon id */
    finibot(id, nazel, iord, nazel);

    /* write header */
    fprintf(outfile, "th(%c):", inunit);
    for (ith = 0; ith < nth; ith++) {
	wrangle(th[ith], inunit, fmt->outprecision, AZEL_STR_LEN, th_str);
	fprintf(outfile, "\t%s", th_str);
    }
    fprintf(outfile, "\n");

    msg("counting pairs ...");

#ifdef TIME
    printf(" timing ... ");
    fflush(stdout);
    time = clock();
#endif

    /* loop over az-el points */
    idi = -1;
    nid = 0;
    np = 0;
    for (iazel = 0; iazel < nazel; iazel++) {
	i = iord[iazel];
	/* skip points outside mask */
	if (id[i] == -1) continue;
	/* new polygon */
	if (id[i] != idi) {
	    idi = id[i];
	    /* reset pair counts to zero */
	    for (ith = 0; ith < nth; ith++) dd[ith] = 0;
	}
//printf(" %d", idi);
	/* az-el neighbours within same polygon */
	for (jazel = iazel + 1; jazel < nazel; jazel++) {
	    j = iord[jazel];
	    /* exit at new polygon */
	    if (id[j] != idi) break;
	    /* 1 - cosl(th_ij) */
	    cmm = cmij(rp[i], rp[j]);
	    /* ith such that cm[ith-1] <= cmm < cm[ith] */
	    ith = search(nth, cm, cmm);
	    /* increment count in this bin */
	    if (ith < nth) dd[ith]++;
	    /* increment total pair count */
	    np++;
	}
	/* write counts for this polygon */
	if (iazel + 1 == nazel || id[iord[iazel + 1]] != idi) {
	    fprintf(outfile, "%d", idi);
	    for (ith = 0; ith < nth; ith++) {
		fprintf(outfile, "\t%d", dd[ith]);
	    }
	    fprintf(outfile, "\n");
	    fflush(outfile);
	    nid++;
//printf("\n");
	}
    }

#ifdef TIME
    time = clock() - time;
    printf("done in %Lg sec\n", (float)time / (float)CLOCKS_PER_SEC);
#else
    msg("\n");
#endif

    /* advise */
    if (outfile != stdout) {
	fclose(outfile);
	msg("%d distinct pairs in %d th-bins x %d polygons written to %s\n", np, nth, nid, out_fn);
    }

    return(np);
}