struct graph;
-struct graph *graph_new(int xdim, int ydim);
+struct graph *graph_new(unsigned int xdim, unsigned int ydim);
void bar_graph_draw(struct graph *g, cairo_t *cr);
void line_graph_draw(struct graph *g, cairo_t *cr);
void line_graph_set_data_count_limit(struct graph *g, int per_label_limit);