tests/math/chart-get-scale-test.c

   1 /* PSPP - a program for statistical analysis.
   2    Copyright (C) 2015 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>. */
  16
  17 #include <config.h>
  18
  19 #include <stdlib.h>
  20 #include <stdbool.h>
  21 #include <assert.h>
  22 #include <string.h>
  23
  24 #include "libpspp/compiler.h"
  25
  26 #include "math/chart-geometry.h"
  27 #include <limits.h>
  28 #include <float.h>
  29 #include <math.h>
  30
  31 #if 0
  32 static void
  33 dump_scale (const double low, const double interval, int n_ticks)
  34 {
  35   int i;
  36   double tick = low;
  37   for (i = 0; i <= n_ticks; ++i)
  38     {
  39       printf ("Tick %d: %g\n", i, tick);
  40       tick += interval;
  41     }
  42 }
  43 #endif
  44
  45
  46 static void
  47 test_range (double low, double high)
  48 {
  49   int n_ticks = 0;
  50   double interval;
  51   double lower;
  52
  53   chart_get_scale (high, low,
  54                    &lower, &interval, &n_ticks);
  55
  56   if ((high - low) < 10 * DBL_MIN){
  57     assert (n_ticks == 0);
  58     assert (lower == low);
  59     assert (interval <= 10 * DBL_MIN);
  60   }
  61   else
  62     assert (n_ticks > 4);
  63
  64   assert (n_ticks <= 10);
  65
  66 #if 0
  67   printf("%s: high: %lg, low %lg, interval: %lg, nticks: %d\n",
  68          __FUNCTION__, high, low, interval, n_ticks);
  69   dump_scale (lower, interval, n_ticks);
  70 #endif
  71
  72   if ((high - low) > 10 * DBL_MIN) {
  73     assert (lower <= low);
  74     assert (lower + interval > low);
  75     assert (lower + n_ticks * interval < high);
  76     assert (lower + (n_ticks + 1) * interval >= high);
  77   }
  78 }
  79
  80
  81 int
  82 main (int argc UNUSED, char **argv UNUSED)
  83 {
  84   test_range (0, 0);
  85   test_range (5, 5);
  86   test_range (-5, -5);
  87   test_range (0, 7);
  88   test_range (0.2, 11);
  89   test_range (-0.2, 11);
  90   test_range (-10, 0.2);
  91   test_range (-10, -0.2);
  92   test_range (-10000, 10003);
  93   test_range (50042,50053);
  94   test_range (-50010, -49999);
  95   test_range (0.000100002, 0.000100010);
  96
  97   test_range (102, 50030);
  98   test_range (0.00102, 0.0050030);
  99
 100   return 0;
 101 }