mgraph(graph_line_colour = "red", graph_curve_x_values = -15.000.0015.00, legend_user_text = " My red curve ", graph_symbol = "on", graph_curve_y_values = 50.0025.0050.00, graph_symbol_marker_index = 15, graph_symbol_colour = "black", graph_symbol_height = 1.00, legend = "on", graph_line_thickness = 8)