Changed all the licence notices in all the files.

[pspp-builds.git] / src / histogram.c

diff --git a/src/histogram.c b/src/histogram.c
index 0d90edd5ec0db23b49039fe20003592dad0413ff..ab258e3301993fd33b83b3bd1e7e36c6a1bcb4c1 100644 (file)
--- a/src/histogram.c
+++ b/src/histogram.c
@@ -14,171 +14,41 @@
 
    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., 59 Temple Place - Suite 330, Boston, MA
-   02111-1307, USA. */
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+   02110-1301, USA. */
 
-#include <config.h>
-
-#include <stdio.h>
-#include <plot.h>
 #include <math.h>
 #include <gsl/gsl_histogram.h>
 #include <assert.h>
-
-#include "hash.h"
-
-#include "var.h"
+#include "histogram.h"
 #include "chart.h"
 
-/* Number of bins in which to divide data */
-#define BINS 7
-
-/* The approximate no of ticks on the y axis */
-#define YTICKS 10
-
-#ifndef M_PI 
-#define M_PI ( 22.0 / 7.0 )
-#endif
-
-
-static double gaussian(double x, double mu, double sigma ) ;
-
-
-static double
-gaussian(double x, double mu, double sigma )
-{
-  return (exp( - (( x - mu )* (x - mu) / (2.0 * sigma * sigma)  ))
-    / ( sigma * sqrt( M_PI * 2.0) ))  ;
-}
-
 
-
-/* Write the legend of the chart */
-void
-histogram_write_legend(struct chart *ch, const struct normal_curve *norm)
-{
-  char buf[100];
-  pl_savestate_r(ch->lp);
-
-  sprintf(buf,"N = %.2f",norm->N);
-  pl_move_r(ch->lp, ch->legend_left, ch->data_bottom);
-  pl_alabel_r(ch->lp,0,'b',buf);
-
-  sprintf(buf,"Mean = %.1f",norm->mean);
-  pl_fmove_r(ch->lp,ch->legend_left,ch->data_bottom + ch->font_size * 1.5);
-  pl_alabel_r(ch->lp,0,'b',buf);
-
-  sprintf(buf,"Std. Dev = %.2f",norm->stddev);
-  pl_fmove_r(ch->lp,ch->legend_left,ch->data_bottom + ch->font_size * 1.5 * 2);
-  pl_alabel_r(ch->lp,0,'b',buf);
-
-  pl_restorestate_r(ch->lp);    
-}
-
-static void hist_draw_bar(struct chart *ch, const gsl_histogram *hist, int bar);
-
-
-static void
-hist_draw_bar(struct chart *ch, const gsl_histogram *hist, int bar)
+gsl_histogram *
+histogram_create(double bins, double x_min, double x_max)
 {
-  double upper;
-  double lower;
-  double height;
-
-  const size_t bins = gsl_histogram_bins(hist);
-  const double x_pos = (ch->data_right - ch->data_left) * bar / (double) bins ;
-  const double width = (ch->data_right - ch->data_left) / (double) bins ;
-
+  int n;
+  double bin_width ;
+  double bin_width_2 ;
+  double upper_limit, lower_limit;
 
-  assert ( 0 == gsl_histogram_get_range(hist, bar, &lower, &upper));
+  gsl_histogram *hist = gsl_histogram_alloc(bins);
 
-  assert( upper >= lower);
 
-  height = gsl_histogram_get(hist, bar) * 
-    (ch->data_top - ch->data_bottom) / gsl_histogram_max_val(hist);
-
-  pl_savestate_r(ch->lp);
-  pl_move_r(ch->lp,ch->data_left, ch->data_bottom);
-  pl_fillcolorname_r(ch->lp, ch->fill_colour); 
-  pl_filltype_r(ch->lp,1);
-
-
-  pl_fboxrel_r(ch->lp,
-              x_pos, 0,
-              x_pos + width, height);
-
-  pl_restorestate_r(ch->lp);
-
-  {
-  char buf[5];
-  snprintf(buf,5,"%g",(upper + lower) / 2.0);
-  draw_tick(ch, TICK_ABSCISSA,
-           x_pos + width / 2.0, buf);
-  }
-
-
-}
-
-
-
-
-void
-histogram_plot(const gsl_histogram *hist,
-              const char *factorname,
-              const struct normal_curve *norm, short show_normal)
-{
-  int i;
-  int bins;
-  
-  struct chart ch;
-
-  bins = gsl_histogram_bins(hist);
-
-  chart_initialise(&ch);
-  chart_write_title(&ch, _("HISTOGRAM"));
-
-  chart_write_ylabel(&ch, _("Frequency"));
-  chart_write_xlabel(&ch, factorname);
-
-  chart_write_yscale(&ch, 0, gsl_histogram_max_val(hist), 5);
-
-  for ( i = 0 ; i < bins ; ++i ) 
-      hist_draw_bar(&ch, hist, i);
-
-  histogram_write_legend(&ch, norm);
-
-  if ( show_normal  )
-  {
-    /* Draw the normal curve */    
-
-    double d ;
-    double x_min, x_max, not_used ;
-    double abscissa_scale ;
-    double ordinate_scale ;
+  bin_width = chart_rounded_tick((x_max - x_min)/ bins);
+  bin_width_2 = bin_width / 2.0;
+    
+  n =  ceil( x_max / (bin_width_2) ) ; 
+  if ( ! (n % 2 ) ) n++;
+  upper_limit = n * bin_width_2;
 
+  n =  floor( x_min / (bin_width_2) ) ; 
+  if ( ! (n % 2 ) ) n--;
+  lower_limit = n * bin_width_2;
 
-    gsl_histogram_get_range(hist, 0, &x_min, &not_used);
-    gsl_histogram_get_range(hist, bins - 1, &x_max, &not_used);
-    
-    abscissa_scale = (ch.data_right - ch.data_left) / (x_max - x_min);
-    ordinate_scale = (ch.data_top - ch.data_bottom) / 
-      gsl_histogram_max_val(hist) ;
+  gsl_histogram_set_ranges_uniform(hist, lower_limit, upper_limit);
 
-    pl_move_r(ch.lp, ch.data_left, ch.data_bottom);    
-    for( d = ch.data_left; 
-        d <= ch.data_right ; 
-        d += (ch.data_right - ch.data_left) / 100.0)
-      {    
-       const double x = (d - ch.data_left) / abscissa_scale + x_min ; 
-       
-       pl_fcont_r(ch.lp,  d, 
-                  ch.data_bottom  + norm->N * ordinate_scale *
-                  gaussian(x, norm->mean, norm->stddev) 
-                  );
-      }
-    pl_endpath_r(ch.lp);
 
-  }
-  chart_finalise(&ch);
+  return hist;
 }