/*****************************************************************************
+** Name: ezsupport.h
+** Function: Support routines for EZPlot library
+** Programmer: Kevin Rosenberg
+** Date Started: 1-22-85
+**
** This is part of the CTSim program
-** Copyright (C) 1983-2000 Kevin Rosenberg
+** Copyright (c) 1983-2001 Kevin Rosenberg
**
-** $Id: ezsupport.cpp,v 1.4 2000/07/13 07:03:21 kevin Exp $
+** $Id$
**
** This program is free software; you can redistribute it and/or modify
** it under the terms of the GNU General Public License (version 2) as
#include "ezplot.h"
-/* NAME
- * axis_scale calculates graph axis scaling
- *
- * SYNOPSIS:
- * retval = axis_scale (min, max, nint, minp, maxp, nintp,
- * rec_total, rec_frac)
- *
- * INPUT:
- * double min Smallest value to plot
- * double max Largest value to plot
- * int nint Number of intervals desired
- *
- * OUTPUT:
- * int retval FALSE if illegal parameters, else TRUE
- * double *minp Minimum graph value
- * double *maxp Maximum graph value
- * int *nintp Number of intervals for graph
- * int *rec_total Recommended field width for printing out the number
- * int *rec_frac Recommended number of digits for print fraction
- */
-
-int
-axis_scale (double min, double max, int nint, double *minp, double *maxp, int *nintp)
-{
- double eps, a, scale, mina, maxa, d, j, e, f, v, wdt, g, h;
-
- if (min >= max || nint < 1) {
- sys_error (ERR_WARNING, "Invalid params: min=%lf, min=%lf, num intervals=%d [axis_scale]", min, max, nint);
- return (FALSE);
- }
-
- eps = 0.025;
- a = fabs(min);
- if (fabs(min) < fabs(max))
- a = fabs(max);
- scale = pow (10.0, floor(log10(a)));
- loop:
- mina = min / scale;
- maxa = max / scale;
- d = (maxa - mina) / nint;
- j = d * eps;
- e = floor (log10(d));
- f = d / pow (10.0, e);
- v = 10.0;
- if (f < sqrt(2.0))
- v = 1.0;
- else if (f < sqrt (10.0))
- v = 2.0;
- else if (f < sqrt (50.0))
- v = 5.0;
- wdt = v * pow (10.0, e);
- g = floor (mina / wdt);
- if (fabs(g + 1 - mina / wdt) < j)
- g = g + 1;
- *minp = wdt * g;
- h = floor (maxa / wdt) + 1.0;
- if (fabs(maxa / wdt + 1 - h) < j)
- h = h - 1;
- *maxp = wdt * h;
- *nintp = static_cast<int>(h - g);
- if (fabs(*maxp) >= 10.0 || fabs(*minp) >= 10.0) {
- scale = scale * 10.0;
- goto loop;
- }
-
- *minp *= scale;
- *maxp *= scale;
-
- return (TRUE);
-}
-
-
-/* NAME
- * make_numfmt Make a numeric format string
- *
- * SYNOPSIS
- * make_numfmt (fmtstr, fldwid, nfrac, min, max, nint)
- * char *fmtstr Returned format string for printf()
- * int *fldwid Returned field width
- * int *nfrac If < 0, then calculate best number of
- * fraction places & return that value
- * If >= 0, then use that number of places
- * double min Minimum value
- * double max Maximum value
- * int nint Number of intervals between min & max
- *
- * DESCRIPTION
- * This routine is written as an INTERNAL routine for EZPLOT
- */
-
-static inline double
-trunc (double x)
-{
- double integer;
-
- modf (x, &integer);
-
- return (integer);
-}
-
-void
-make_numfmt (char *fmtstr, int *fldwid, int *nfrac, double minval, double maxval, int nint)
-{
- int wid, frac, expon;
-
- double delta = (maxval - minval) / nint;
- double absmin = fabs(minval);
- double absmax = fabs(maxval);
- double logt = log10( max(absmin, absmax) );
-
- if (fabs(logt) >= 6) { /* use exponential format */
- if (fabs(logt) > 99)
- expon = 5; /* E+102 */
- else
- expon = 4; /* E+00 */
-
- if (*nfrac < 0) { /* calculate frac */
- delta /= pow (10., floor(logt)); /* scale delta */
- frac = static_cast<int>(fabs(trunc(log10(delta)))) + 1;
- if (frac < 1)
- frac = 1; /* to be safe, add decimal pt */
- } else /* use users' frac */
- frac = *nfrac;
-
- wid = 2 + frac + expon;
- if (minval < 0. || maxval < 0.)
- ++wid;
- sprintf (fmtstr, "%s%d%s%d%s", "%", wid, ".", frac, "g");
- } else { /* use fixed format */
- wid = static_cast<int>(trunc(logt)) + 1;
- if (wid < 1)
- wid = 1;
- if (minval < 0. || maxval < 0.)
- ++wid;
-
- if (*nfrac < 0) { /* calculate frac */
- if (delta >= 0.999999)
- frac = 1; /* add a decimal pt to be safe */
- else
- frac = static_cast<int>(fabs(trunc(log10(delta)))) + 1;
- } else /* use users' frac */
- frac = *nfrac;
-
- wid += 1 + frac;
- sprintf (fmtstr, "%s%d%s%d%s", "%", wid, ".", frac, "f");
- }
-
- *fldwid = wid;
- *nfrac = frac;
-}
-
-#ifdef TEST
-int
-main (void)
-{
- double min, max;
- double x, xinc;
- int i, nint, wid, frac;
- char fmtstr[10];
-
- printf ("Enter min, max, & number of intervals -- ");
- scanf ("%lf %lf %d", &min, &max, &nint);
-
- frac = -1; /* let makefmt determine fraction */
-
- makefmt (fmtstr, &wid, &frac, min, max, nint);
-
- printf ("Format string = %s\n", fmtstr);
-
- xinc = (max - min) / nint;
-
- x = min;
- for (i = 0; i <= nint; i++) {
- printf (fmtstr, x);
- x += xinc;
- printf ("\n");
- }
-}
-#endif
-
-void
-ezplot_1d (double *y, int n)
-{
- double x [n];
-
- for (int i = 0; i < n; i++)
- x[i] = i;
-
- ezplot (x, y, n);
-}
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