Function gmt_sprintf_float

src/gmt_support.c:12104–12173

! . */

/*! . */
void gmt_sprintf_float (struct GMT_CTRL *GMT, char *string, char *format, double x) {
	/* Determines if %-apostrophe is used in the format for a float. If so, must temporarily switch to LC_NUMERIC=en_US */
	char *use_locale = strstr (format, "%'");
#ifdef HAVE_SETLOCALE
	if (use_locale) setlocale (LC_NUMERIC, "en_US");
#endif
	if (GMT->current.plot.substitute_pi) {	/* Want to use pi when close to known multiples of pi. This variable is set per axis in gmt_xy_axis */
		/* Any fraction of pi up to 1/20th allowed.
		 * substitute_pi becomes true when items with "pi" are used in -R, -I etc. */
		int k = 1, m, n;
		char fmt[GMT_LEN16] = {""};
		double f = fabs (x / M_PI);		/* Float multiples of pi */
		if (fabs (f) < GMT_CONV4_LIMIT) {	/* Deal with special case of zero pi */
			sprintf (string, "0");
			return;
		}
		gmtsupport_make_fraction (GMT, f, 20, &n, &m);	/* Max 20th of pi */
		string[0] = (x < 0.0) ? '-' : '+';	/* Place leading sign */
		string[1] = '\0';			/* Chop off old string */
		if (n > 1) {	/* Need an integer in front of pi */
			k += snprintf (fmt, GMT_LEN16, "%d", n);
			strcat (string, fmt);
			//k += irint (floor (log10 ((double)n))) + 1;	/* Add how many decimals needed for n */
		}
		strcat (string, "@~p@~");	/* Place the pi symbol */
		k += 5;	/* Add number of characters just placed to print pi */
		if (m > 1) {	/* Add the fractions part */
			k += snprintf (fmt, GMT_LEN16, "/%d", m);
			strcat (string, fmt);
			//k += irint (floor (log10 ((double)m))) + 2;	/* Add how many decimals needed for /m */
		}
		string[k] = '\0';	/* Truncate any old string */
		//fprintf (stderr, "f = %g n = %d  m = %d.  String = %s\n", f, n, m, string);
	}
	else
#ifndef WIN32
		sprintf (string, format, x);
#else
	{	/* Windows doesn't support %' format */
		if (use_locale) {
			char *new_format = gmt_strrep(format, "%'", "%");
			sprintf (string, new_format, x);
			gmt_M_str_free (new_format);
		} else
			sprintf (string, format, x);
	}
#endif
	if (use_locale) {
#ifdef HAVE_SETLOCALE
		setlocale (LC_NUMERIC, "C");	/* Undo the damage */
#endif
		if (strchr (string, ',') == NULL && fabs (x) > 1000.0 && fabs (x - irint (x)) < GMT_CONV8_LIMIT) {
			/* System not capable of printf groups for integers so we insert those commas manually... */
			char *tmp = strdup (string);
			int n = 0, olen = (int)strlen (tmp), k = (x < 0) ? 1 : 0;
			int nlen = olen + irint (floor (log10(fabs(x))/3.0));	/* Number of commas added */
			string[nlen] = '\0';
			/* We guild the string from back to front */