-/* PSPP - computes sample statistics.
+/* PSPP - a program for statistical analysis.
Copyright (C) 2004 Free Software Foundation, Inc.
- This program is free software; you can redistribute it and/or
- modify it under the terms of the GNU General Public License as
- published by the Free Software Foundation; either version 2 of the
- License, or (at your option) any later version.
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
- This program is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- General Public License for more details.
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
#include <math.h>
#include "chart-geometry.h"
+static const double standard_ticks[] = {1, 2, 5, 10};
+
+
/* Adjust tick to be a sensible value
ie: ... 0.1,0.2,0.5, 1,2,5, 10,20,50 ... */
double
-chart_rounded_tick(double tick)
+chart_rounded_tick (double tick)
{
-
int i;
double diff = DBL_MAX;
double t = tick;
- static const double standard_ticks[] = {1, 2, 5, 10};
+ double factor;
- const double factor = pow(10,ceil(log10(standard_ticks[0] / tick))) ;
+ /* Avoid arithmetic problems with very small values */
+ if (fabs (tick) < DBL_EPSILON)
+ return 0;
+
+ factor = pow (10,ceil (log10 (standard_ticks[0] / tick)));
for (i = 3 ; i >= 0 ; --i)
{
- const double d = fabs( tick - standard_ticks[i] / factor ) ;
+ const double d = fabs (tick - standard_ticks[i] / factor);
if ( d < diff )
{
}
return t;
-
}