说明：  已知经纬度绘制世界海岸线地图。 如果type_map=0，只绘制海岸线，当 type_map=1，填充低精度的地图
(Create a basemap of the world coastlines. Note that latitude % and longitude RANGES are specified, rather than maximum values. % If type_map=0, only coastlines are drawn. For type_map equal % to 1, a slightly lower resolution shaded map is drawn. The % coastlines and fill color is blue by default, but can be changed % with the input string variable, color.)