Our last major step in choosing a battle strategy is to assess its viability in light of the resource constraints imposed upon our forces. We can accomplish this by taking our best plans, calculating the costs associated with executing them, and then comparing those costs to the resources that we have available.

For the time being, suppose we have decided to explore the possibilities of a 7-day fire attack on the 10,000 strong Wei army 255 miles away at Anding. Also assume that we have already predicted the conditions necessary for a rating of 80, as demonstrated:

> #custom function that calculates the number of Shu soldiers
needed to execute a given fire attack
> functionFireShuSoldiers <- function(rating, execution, duration,
WeiSoldiers) {
+ (rating - 37 - 56 * execution +
+ 1.24 * duration) /
+ (0.00000013 * - WeiSoldiers)
+ }
> #assuming successful execution, how many Shu soldiers would be
needed to lead a fire attack against the 10,000 Wei soldiers
stationed 225 miles away at Anding?
> functionFireShuSoldiers(80, 1, 7, 15000)
[1] 2215.385

Through this process, we determined that 2,215 Shu soldiers must successfully launch the 7-day fire attack to meet our Rating threshold of 80.

Our next step is to take this information and examine its viability in terms of the resources that have been allotted to us.