maptools

I would like to use R to generate a very basic world map with a specific set of countries filled with a red colour to indicate that they are malaria endemic countries. I have a list of these countries in a data frame but am struggling to overlay them on a world map. I have tried using the wrld_simpl object and also the joinCountryData2Map method in the rworldmap package. I would comment on this answer to prevent addition of a possibly redundant question but I do not have enough reputation at the moment, apologies for this. https://stackoverflow.com/a/9102797/1470099 I am having difficulty

I would like simply delete some polygons from a SpatialPolygonsDataFrame object based on corresponding attribute values in the @data data frame so that I can plot a simplified/subsetted shapefile. So far I haven't found a way to do this. For example, let's say I want to delete all polygons from this world shapefile that have an area of less than 30000. How would I go about doing this? Or, similarly, how can I delete Antartica? require(maptools) getinfo.shape("TM_WORLD_BORDERS_SIMPL-0.3.shp") # Shapefile type: Polygon, (5), # of Shapes: 246 world.map <- readShapeSpatial("TM_WORLD_BORDERS_SIMPL