void gtk_chart_set_overdrawn(GtkChart * chart, gdouble minimum);
//void gtk_chart_set_every_xval(GtkChart * chart, gint decay);
void gtk_chart_set_barw(GtkChart * chart, gdouble barw);
void gtk_chart_set_overdrawn(GtkChart * chart, gdouble minimum);
//void gtk_chart_set_every_xval(GtkChart * chart, gint decay);
void gtk_chart_set_barw(GtkChart * chart, gdouble barw);