C++ Primer Plus

Changing the Implementation

There may be something about the program output, aside from Fluffy the Cat’s lack of financial acumen, that bothers you—the somewhat inconsistent formatting of the numbers. Here’s an opportunity to refine an implementation while keeping the interface unchanged. The ostream class included member functions that control formatting. Without going into much detail, you can avoid e-notation by using the setf() method much as we did in Listing 8.8:

std::cout.setf(std::ios_base::fixed, std::ios_base::floatfield);

This sets a flag in the cout object instructing cout to use fixed-point notation. Similarly, the following statement causes cout to show three places to the right of the decimal when using fixed-point notation: