In a Topographic map, here are the programming values of each of that navgations:
N = positive value to the latitude
S= Negative value to the Latitude
W = Positive value to the longitude
E = Negative value to the longitude
Most programmers that work to create the topographic map choose to simply ommit the N,S,W,&E because it will save them a lot of time from having to type in a minus sign before most of their longitude values in code writing.