Conditional Plural Data Processing
Calculating rates can be done in
using plurals for Mary and Sam, i.e.
rate$ = efforts$ / time$
However, this statement commands the computer to perform this
operation for ALL rows. The "combined" row is a problem. While
the effort value is given, the time value is not. So this
computation can not be performed. If the computer is commanded to
do so under these conditions, unpredictable results may occur.
The solution is a "conditional execution" statement which
restricts the computation to only specified rows. The format of
the statement is :
For a, b, ... , c:
statement1
statement2
:
statementn;
This statement tells the computer to execute the following n
statements only for the named rows. For example:
For sam, mary:
rate$ = efforts$ / time$;
This statement allows the together problem to be solved using sequential plural
statements as follows:
For Sam, Mary:
rate$ = effort$ / time$;
combined rate = sam's rate + mary's rate
combined time = combined effort / combined rate
See Statement syntax and scope for more details.