Internally-stored scan-lines for line-printer mapping

Despite the generally poor graphic-arts quality of the resulting maps, computer-mapping programs using the line-printer for display will probably retain their importance for producing automated rough-copy maps. These programs utilize the almost universally available printers or typewriter terminals. Plotters, cathode ray tubes, and COM units can usually produce maps with more pleasing designs, but the cost of these peripherals is often prohibitive for agencies with relatively small budgets. This paper describes several procedures for increasing the efficiency of line-printer choroplethic mapping when the same areal units are to be used for many maps in a series. The most significant of these modifications to Scripter's CMAP program is a method for storing the geographic base-map data within the program itself, thereby reducing both the number of cards that must be handled by the user and the computer-usage costs. Flow diagrams and a sample subprogram are presented and explained in order to assist the user in making these alterations.