Figure 1. Basic components of a digital geographic information system. 
V 
Polygon Map File 
[in longitude & latitude) 
direction of digitization 
CONVERSION TO 
ALBERS MAP PROJECTION 
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V 
Address Map File 
(in Albers addresses) 
RASTERIZATION PROCESS 
V 
Rasterized Map File 
[filled-in gridded map) 
Figure 2. Steps involved in the conversion of a polygonal map file 
to a rasterized (cellular) map file. 
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