void graph_title(struct graph *g, const char *title);
/* graph_title() sets the main title of the graph to the given string */
void graph_x_title(struct graph *g, const char *title);
/* graph_x_title() sets the title of the x axis to the given string */
void graph_y_title(struct graph *g, const char *title);
/* graph_y_title() sets the title of the y axis to the given string */
void graph_title(struct graph *g, const char *title);
/* graph_title() sets the main title of the graph to the given string */
void graph_x_title(struct graph *g, const char *title);
/* graph_x_title() sets the title of the x axis to the given string */
void graph_y_title(struct graph *g, const char *title);
/* graph_y_title() sets the title of the y axis to the given string */