Labeled Multiple Charts

The above is an example of plural data using labeled three dimensional charts. The second type of multiple chart problems discussed in this chapter requires another form of three dimensional chart just to organize the data. These problems are characterized by giving two sets of relational facts such that each set requires its own chart. However, a solution can be obtained only by relating the two charts. Since each chart is a plane in the three dimensional problem, the equation that relates the charts is called a "plane equation." These problems are called relational relational problems. In these problems, the row labels are the same for the two planes so a diagram sketch is not required. However, since these three dimensional problems have two charts with the same entry names. In order to distinguish between them, the two charts must be labeled with different names in the upper left hand corners of the charts. As an example of this type of problem consider: Example d. : Ann is fifteen years older than Joe. Ten years from now, Ann will be twice as old as Joe. How old is each now? One chart is set up for the current or "now" age relationship and one chart is set up for the second or "then" relationship. The two charts are: now unknown factor term age ann u 1 15 u+15 joe u 1 0 u then unknown factor age ann u+10 2 2(u+10) joe u+10 1 u+10 The possessive form of the chart names can be used to identify specific values in the program. For example, the value for "ann's factor" is ambiguous since applies to in both charts. However, "now's Ann's factor" and "then's Ann's factor" are unique (The alternative notation "Ann's now factor" and "Ann's then factor" are a little more readable in this case. Either form is acceptable.) Whenever two or more tables are used in one program with out a label table, they must be labeled. For clarity's sake, all value references must include chart names even if the reference appears in only one chart and is unique. For example, "now's ann's term" must be used not just "ann's term". When many charts are present, the use of the charts name is necessary to make it easy to find, so the convention is to always use it. The name of the chart can also be used for statements. For example, for ann and joe: would have the scope of all "ann"s and "joe"s in all tables. While for now's ann and joe: restricts the scope to the now table. The table name may be used alone to refer to entire charts. Multiple tables and entries may be named. Examples: for now: for now and then: for now, then and ago: for now's and then's ann$ and joe$: for now's, then's and ago's ann$, bill$ and joe$: