1 /* PSPP - a program for statistical analysis.
2 Copyright (C) 2014 Free Software Foundation, Inc.
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.
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.
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/>. */
19 #include "output/charts/scatterplot.h"
21 #include "data/case.h"
22 #include "data/casereader.h"
23 #include "data/variable.h"
24 #include "output/cairo-chart.h"
25 #include "libpspp/str.h"
26 #include "libpspp/message.h"
29 #define _(msgid) gettext (msgid)
33 xrchart_draw_scatterplot (const struct chart_item *chart_item, cairo_t *cr,
34 struct xrchart_geometry *geom)
36 const struct scatterplot_chart *spc = to_scatterplot_chart (chart_item);
37 struct casereader *data;
39 /* While reading the cases, a list with categories of the byvar is build */
40 /* All distinct values are stored in catvals */
41 /* Each category will later have a different plot colour */
42 const int MAX_PLOT_CATS = 20;
43 union value catvals[MAX_PLOT_CATS];
47 const struct xrchart_colour *colour;
50 byvar_width = var_get_width(spc->byvar);
52 xrchart_write_xscale (cr, geom,
55 xrchart_write_yscale (cr, geom, spc->y_min, spc->y_max);
56 xrchart_write_title (cr, geom, _("Scatterplot %s"), chart_item->title);
57 xrchart_write_xlabel (cr, geom, var_to_string(spc->xvar));
58 xrchart_write_ylabel (cr, geom, var_to_string(spc->yvar));
61 data = casereader_clone (spc->data);
62 for (; (c = casereader_read (data)) != NULL; case_unref (c))
66 const union value *val = case_data(c,spc->byvar);
67 for(i=0;i<n_catvals && !value_equal(&catvals[i],val,byvar_width);i++);
68 if (i == n_catvals) /* No entry found */
70 if (n_catvals < MAX_PLOT_CATS)
73 ds_init_empty(&label);
74 if (var_is_value_missing(spc->byvar,val,MV_ANY))
75 ds_put_cstr(&label,"missing");
77 var_append_value_name(spc->byvar,val,&label);
78 value_clone(&catvals[n_catvals++],val,byvar_width);
80 geom->dataset = xrealloc (geom->dataset,
81 geom->n_datasets * sizeof (*geom->dataset));
83 geom->dataset[geom->n_datasets - 1] = strdup(ds_cstr(&label));
86 else /* Use the last plot category */
88 *(spc->byvar_overflow) = true;
93 colour = &data_colour [ i % XRCHART_N_COLOURS];
94 cairo_set_source_rgb (cr,
96 colour->green / 255.0,
97 colour->blue / 255.0);
99 xrchart_datum (cr, geom, 0,
100 case_data (c, spc->xvar)->f,
101 case_data (c, spc->yvar)->f);
103 casereader_destroy (data);
106 for(i=0;i<n_catvals;i++)
107 value_destroy(&catvals[i],byvar_width);
110 xrchart_write_legend(cr, geom);
114 // xrchart_line (cr, geom, npp->slope, npp->intercept,
115 // npp->y_first, npp->y_last, XRCHART_DIM_Y);