CS 107 - Lab 9

Creating the Class Point

A C++ class allows a program to take advantage of the object-oriented features of the language. A class has both data members and methods. The data members are the values that define the instance of the class. The methods are operations (functions) that use the class. Most often, the data members are private (can only be accessed inside of the class) while the members are public (can be accessed either inside or outside of the class).

During lecture, we have been creating a class Complex. Refer to this class and the discussion from lecture to complete this lab.

Lab Assignment

Due: By your Lab Time during the eleventh week of the semester (the week of 3/31/2003).

You may turn in the assignment to your TA during lab or place it in his mailbox in 905 SEO. It is suggested that you place it in his mailbox just in case you are unable to attend lab. You are to hand in a print out of your program to do the following to your TA.

Add to the C++ program lab9.cpp a class with the name of Point. Note that the first letter is in upper case.
This point class is to have two private data members that store the X and Y coordinates of a point in a Cartesian coordinate graph. You may name these data members anything that you like. To keep things simple, these data member will store integer values.
This point class is to have the following public methods:
- setX()
  This method is to take one integer parameter and store its value into the data member for the X coordinate. This method is not to return any value.
- setY()
  This method is to take one integer parameter and store its value into the data member for the Y coordinate. This method is not to return any value.
- setXY()
  This method is to take two integer parameters and store the first parameter value into the data member for the X coordinate and store the second parameter value into the data member for the Y coordinate. This method is not to return any value.
- getX()
  This method is to have no parameters and it to return the value of the data member for the X coordinate.
- getY()
  This method is to have no parameters and it to return the value of the data member for the Y coordinate.
- printPoint()
  This method is to have no parameters and it is not to return any value. This method is to print to cout the values for the X and Y coordinate within parenthesis and separated by a comma. This means in the form of:
```
     (X,Y)
```
- getQuadrant()
  This method is to have no parameters and is to return an integer value. If the point has X coordinate greater than zero and Y coordinate greater than zero, the point is in quadrant 1 and the method is to return the value of 1. If the point has X coordinate less than zero and Y coordinate greater than zero, the point is in quadrant 2 and the method is to return the value of 2. If the point has X coordinate less than zero and Y coordinate less than zero, the point is in quadrant 3 and the method is to return the value of 3. If the point has X coordinate greater than zero and Y coordinate less than zero, the point is in quadrant 4 and the method is to return the value of 4. If the point has X coordinate equal to zero or Y coordinate equal to zero, the point is not in any quadrant and the method is to return the value of 0.
- distanceFrom()
  This method is to take one parameter of type Point and to return a floating point number. The return value is to be the distance from the point specified in the instance of the class the method is called with and the point specified by the parameter. The formula for this is given as follows. The formula assumes the X and Y coordinates for the two points are specified by x1, y1, x2 and y2, where the two points are (x1,y1) and (x2,y2).
```
     distance = SQRT( (x1-x2)² + (y1-y2)² )
```

The following is the code in the file lab9.cpp. The file is also available from the ~troy directory on icarus. To copy the file from the ~troy directory on icarus to your current directory on icarus type "cp ~troy/lab9.cpp .".


#include <iostream>

// put your Point class here

int main()
{
 Point pt1, pt2, pt3, origin;

 pt1.setX(5);
 pt1.setY(7);

 cout << "Point pt1 is: (" << pt1.getX() << "," pt1.getY() << ")" << endl;
 cout << "Point pt1 is in quadrant " << pt1.getQuadrant() << endl;

 pt2.setXY (-2, -4);
 pt3.setXY (-8, 9);
 origin.setXY (0, 0);

 cout << "Point pt2 is: ";
 pt2.printPoint();
 cout << endl;
 cout << "Point pt2 is in quadrant " << pt2.getQuadrant() << endl;

 cout << "Point pt3 is: ";
 pt3.printPoint();
 cout << endl;
 cout << "Point pt3 is in quadrant " << pt3.getQuadrant() << endl;

 cout << "Point origin is: ";
 origin.printPoint();
 cout << endl;
 cout << "Point origin is in quadrant " << origin.getQuadrant() << endl;

 cout << "The distance between pt1 and pt2 is " << pt1.distanceFrom (pt2)
      << endl;
 cout << "The distance between pt2 and pt1 is " << pt2.distanceFrom (pt1)
      << endl;
 cout << "The distance between pt3 and the origin is " 
      << pt3.distanceFrom (origin) << endl;
 cout << "The distance between the origin and pt3 is " 
      << origin.distanceFrom (pt3) << endl;
}

Hand in a print out of your program to your TA.