/AND MAXIMUM NUMBER OF PEAS IN A POD.9 INT MAIN( )10 {THIS VARIABLE...

8 //and maximum number of peas in a pod.9 int main( )10 {This variable named11 int maxCount, minCount, podCount;averagePea is local to the12 double averagePea, yield;main function.13 cout << "Enter minimum and maximum number of peas in a pod: ";14 cin >> minCount >> maxCount;15 cout << "Enter the number of pods: ";16 cin >> podCount;17 cout << "Enter the weight of an average pea (in ounces): ";18 cin >> averagePea;19 yield =20 estimateOfTotal(minCount, maxCount, podCount) * averagePea;21 cout.setf(ios::fixed);22 cout.setf(ios::showpoint);23 cout.precision(3);24 cout << "Min number of peas per pod = " << minCount << endl25 << "Max number of peas per pod = " << maxCount << endl26 << "Pod count = " << podCount << endl27 << "Average pea weight = "28 << averagePea << " ounces" << endl29 << "Estimated average yield = " << yield << " ounces"30 << endl;31 return 0;32 }3334 double estimateOfTotal(int minPeas, int maxPeas, int podCount)35 {36 double averagePea;averagePea is local tothe function estimateOfTotal.37 averagePea = (maxPeas + minPeas)/2.0;38 return (podCount * averagePea);39 }

Scope Rules 119

Display 3.8 Local Variables (part 2 of 2)SAMPLE DIALOGUEEnter minimum and maximum number of peas in a pod: 4 6Enter the number of pods: 10Enter the weight of an average pea (in ounces): 0.5Min number of peas per pod = 4 Max number of peas per pod = 6Pod count = 10 Average pea weight = 0.500 ouncesEstimated average yield = 25.000 ounces

When the variable

^averagePea

is given a value in the function call to

estimateOfTotal

,

this does not change the value of the variable in the

^main

function that is also named

averagePea

.

Variables that are declared within the body of a function definition are said to be

local variablelocal to that function or to have that function as their scope. If a variable is local to

some function, we sometimes simply call it a local variable, without specifying the

scope

function.

Another example of local variables can be seen in Display 3.5. The definition of the

function

^totalCost

in that program begins as follows:

double totalCost(int numberParameter, double priceParameter){ const double TAXRATE = 0.05; //5% sales tax double subtotal;

The variable

^subtotal

is local to the function

^totalCost

. The named constant

^TAXRATE

is also local to the function

^totalCost

. (A named constant is in fact nothing but a vari-

able that is initialized to a value and that cannot have that value changed.)

L

OCAL

V

ARIABLESVariables that are declared within the body of a function definition are said to be local to that functionor to have that function as their scope

.

If a variable is local to a function, then you can have another variable (or other kind of item) with the same name that is declared in another func-tion definition; these will be two different variables, even though they have the same name. (In particular, this is true even if one of the functions is the main function.)