X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Foutput%2Fcharts%2Fplot-hist-cairo.c;h=a85471962fcbebf52ff445190766d049781244f4;hb=e0c5553451a33f2f3bcbd877da0b0e8551d09ff8;hp=7e2afee9b022cc621578623c889a474ad7b033dc;hpb=d3487b8eeb911e0547acf72fe4481338d78d0721;p=pspp diff --git a/src/output/charts/plot-hist-cairo.c b/src/output/charts/plot-hist-cairo.c index 7e2afee9b0..a85471962f 100644 --- a/src/output/charts/plot-hist-cairo.c +++ b/src/output/charts/plot-hist-cairo.c @@ -69,30 +69,24 @@ histogram_write_legend (cairo_t *cr, const struct xrchart_geometry *geom, static void hist_draw_bar (cairo_t *cr, const struct xrchart_geometry *geom, - const gsl_histogram *h, int bar, const char *tick_format_string, - const double tickscale, const bool tickoversize) + const gsl_histogram *h, int bar) { double upper; double lower; double height; - const size_t bins = gsl_histogram_bins (h); - - const double x_pos = - (geom->axis[SCALE_ABSCISSA].data_max - geom->axis[SCALE_ABSCISSA].data_min) * - bar / (double) bins ; - - const double width = - (geom->axis[SCALE_ABSCISSA].data_max - geom->axis[SCALE_ABSCISSA].data_min) / (double) bins ; - assert ( 0 == gsl_histogram_get_range (h, bar, &lower, &upper)); - assert ( upper >= lower); + const double x_pos = + (lower - geom->axis[SCALE_ABSCISSA].min) * geom->axis[SCALE_ABSCISSA].scale + + geom->axis[SCALE_ABSCISSA].data_min; + const double width = (upper - lower) * geom->axis[SCALE_ABSCISSA].scale; + height = geom->axis[SCALE_ORDINATE].scale * gsl_histogram_get (h, bar); cairo_rectangle (cr, - geom->axis[SCALE_ABSCISSA].data_min + x_pos, + x_pos, geom->axis[SCALE_ORDINATE].data_min, width, height); cairo_save (cr); @@ -103,10 +97,6 @@ hist_draw_bar (cairo_t *cr, const struct xrchart_geometry *geom, cairo_fill_preserve (cr); cairo_restore (cr); cairo_stroke (cr); - - draw_tick (cr, geom, SCALE_ABSCISSA, tickoversize, - x_pos + width / 2.0, tick_format_string, (upper+lower)/2.0*tickscale); - } void @@ -116,11 +106,6 @@ xrchart_draw_histogram (const struct chart_item *chart_item, cairo_t *cr, struct histogram_chart *h = to_histogram_chart (chart_item); int i; int bins; - char *tick_format_string; - char *test_text; - double width, left_width, right_width, unused; - double tickscale; - bool tickoversize; xrchart_write_title (cr, geom, _("HISTOGRAM")); @@ -134,27 +119,17 @@ xrchart_draw_histogram (const struct chart_item *chart_item, cairo_t *cr, } xrchart_write_yscale (cr, geom, 0, gsl_histogram_max_val (h->gsl_hist)); + xrchart_write_xscale (cr, geom, gsl_histogram_min (h->gsl_hist), + gsl_histogram_max (h->gsl_hist)); + /* Draw the ticks and compute if the rendered tick text is wider than the bin */ bins = gsl_histogram_bins (h->gsl_hist); - tick_format_string = chart_get_ticks_format (gsl_histogram_max (h->gsl_hist), - gsl_histogram_min (h->gsl_hist), - bins, - &tickscale); - test_text = xasprintf(tick_format_string, gsl_histogram_max (h->gsl_hist)*tickscale); - xrchart_text_extents (cr, geom, test_text, &right_width, &unused); - free(test_text); - test_text = xasprintf(tick_format_string, gsl_histogram_min (h->gsl_hist)*tickscale); - xrchart_text_extents (cr, geom, test_text, &left_width, &unused); - free(test_text); - width = MAX(left_width, right_width); - tickoversize = width > 0.9 * - ((double)(geom->axis[SCALE_ABSCISSA].data_max - geom->axis[SCALE_ABSCISSA].data_min))/bins; + for (i = 0; i < bins; i++) { - hist_draw_bar (cr, geom, h->gsl_hist, i, tick_format_string, tickscale, tickoversize); + hist_draw_bar (cr, geom, h->gsl_hist, i); } - free(tick_format_string); histogram_write_legend (cr, geom, h->n, h->mean, h->stddev); @@ -162,31 +137,28 @@ xrchart_draw_histogram (const struct chart_item *chart_item, cairo_t *cr, && h->n != SYSMIS && h->mean != SYSMIS && h->stddev != SYSMIS) { /* Draw the normal curve */ - double d; - double x_min, x_max, not_used; - double abscissa_scale; + double x_min, x_max; double ordinate_scale; - double range; + double binwidth; + double x; - gsl_histogram_get_range (h->gsl_hist, 0, &x_min, ¬_used); - range = not_used - x_min; - gsl_histogram_get_range (h->gsl_hist, bins - 1, ¬_used, &x_max); + gsl_histogram_get_range (h->gsl_hist, 0, &x_min, &x_max); + binwidth = x_max - x_min; - abscissa_scale = (geom->axis[SCALE_ABSCISSA].data_max - geom->axis[SCALE_ABSCISSA].data_min) / (x_max - x_min); - ordinate_scale = (geom->axis[SCALE_ORDINATE].data_max - geom->axis[SCALE_ORDINATE].data_min) / - gsl_histogram_max_val (h->gsl_hist); + /* The integral over the histogram is binwidth * sum(bin_i), while the integral over the pdf is 1 */ + /* Therefore the pdf has to be scaled accordingly such that the integrals are equal */ + ordinate_scale = binwidth * gsl_histogram_sum(h->gsl_hist); cairo_move_to (cr, geom->axis[SCALE_ABSCISSA].data_min, geom->axis[SCALE_ORDINATE].data_min); - for (d = geom->axis[SCALE_ABSCISSA].data_min; - d <= geom->axis[SCALE_ABSCISSA].data_max; - d += (geom->axis[SCALE_ABSCISSA].data_max - geom->axis[SCALE_ABSCISSA].data_min) / 100.0) + for (x = geom->axis[SCALE_ABSCISSA].min; + x <= geom->axis[SCALE_ABSCISSA].max; + x += (geom->axis[SCALE_ABSCISSA].max - geom->axis[SCALE_ABSCISSA].min) / 100.0) { - const double x = (d - geom->axis[SCALE_ABSCISSA].data_min) / abscissa_scale + x_min; - const double y = h->n * range * - gsl_ran_gaussian_pdf (x - h->mean, h->stddev); - - cairo_line_to (cr, d, geom->axis[SCALE_ORDINATE].data_min + y * ordinate_scale); - + const double y = gsl_ran_gaussian_pdf (x - h->mean, h->stddev) * ordinate_scale; + /* Transform to drawing coordinates */ + const double x_pos = (x - geom->axis[SCALE_ABSCISSA].min) * geom->axis[SCALE_ABSCISSA].scale + geom->axis[SCALE_ABSCISSA].data_min; + const double y_pos = (y - geom->axis[SCALE_ORDINATE].min) * geom->axis[SCALE_ORDINATE].scale + geom->axis[SCALE_ORDINATE].data_min; + cairo_line_to (cr, x_pos, y_pos); } cairo_stroke (cr); }