Well, let me try to help if I can.
First of all consider a class like this:
class myClass {
private:
int data;
public:
myClass() {};
~myClass() {};
int getData() {return data;}
void setData(int newData) {data=newData;}
void calculateRoot(int amount) {data=sqrt(amount);}
};
An accessor method is used when another method needs the value contained in a private data member of the class. An example of this would be
myClass::getData(), because all it does is return the value of the
data. This type of function is useful for making a read-only variable.
Modify methods would be a method that modifies a private data member inside a class. An example of this would be
myClass::setData(), because it changes the value of
data. Now, you may be wondering why you would use a public member function to modify a private member. Why not just make the data member public?
Well, the whole goal of object-oriented programming is to make classes relatively independant objects. In other words, if you suddenly want
data to equal the value+1, the only things you should have to change is within the class itself. By changing the setter method, the whole thing is changed. If you had manually set the values from other classes, you would suddenly find yourself facing a whole ton of coding. Another good example of this is if you need to change data types in a class.
Finally... managerial functions. I've never heard such a description of them before, so I'm only guessing. I suppose it's a function that manages an object, such as constructors/destructors (memory management), or something such as a function that does more than simply modify a value in an object.
For more information on these topics, I suggest you visit the following sites:
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