williams-et-al-1983-apple-ii-computer-graphics

11Graphs and ChartsObjectivesAfter reading Chapter 11 you should be able to:• Have your computer draw a bar, line, or circle graph using our programsand your data.• Use the computer to graph your own equations.• Label your graphs.Processing data, or "number crunching" as it is sometimes called, haslong been one of the strengths of the computer. In earlier machines, theresults of the processing were all too often only pages and pages of numbers.Long columns of numbers often obscure the meaning those samefigures are supposed to convey, so displaying data in graphic form is animportant tool. Bar charts, line graphs, and circle graphs are the three mostcommonly used display methods, and we will give at least one example ofeach in this chapter. In three of the fo ur examples, the data to be graphedis contained in BASIC DATA statements so that you need only replace thesample data with yours, and the program will graph your data. The otherexample graphs a mathematical equation over a specified range. Modifyingthat program will require you to change the fo rmula and the scalingfactors. We will talk more about each example when the time comes.Belly Up to the BarListing 11- 1 creates a bar graph-with the bars running either vertically orhorizontally. Key the program in and run it. As usual, you may omit any oral I of the REM statements.119