eecs2030.lab2

Class Point2

java.lang.Object

eecs2030.lab2.Point2

public class Point2
extends java.lang.Object

A simple class for representing points in 2D Cartesian coordinates. Every Point2D instance has an x and y coordinate.

Author:

EECS2030 Fall 2016

Constructor Summary

Constructors

Constructor and Description
Point2() Create a point with coordinates (0, 0).
Point2(double newX, double newY) Create a point with coordinates (newX, newY).
Point2(Point2 other) Create a point with the same coordinates as other.

Method Summary

Modifier and Type	Method and Description
Point2	add(Vector2 v) Adds a vector to this point changing the coordinates of this point.
boolean	equals(java.lang.Object obj) Compares this point with the given object.
double	getX() Returns the x-coordinate of this point.
double	getY() Returns the y-coordinate of this point.
int	hashCode() Returns a hash code for this point
void	set(double newX, double newY) Sets the x-coordinate and y-coordinate of this point to newX and newY, respectively.
void	setX(double newX) Sets the x-coordinate of this point to newX.
void	setY(double newY) Sets the y-coordinate of this point to newY.
boolean	similarTo(Point2 other, double tol) Determines if two points are almost equal (similar).
static Vector2	subtract(Point2 a, Point2 b) Returns a new Point2 equal to a - b.
java.lang.String	toString() Returns a string representation of this point.

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

Point2

public Point2()

Create a point with coordinates (0, 0).

Point2

public Point2(double newX,
              double newY)

Create a point with coordinates (newX, newY).

Parameters:

newX - the x-coordinate of the point

newY - the y-coordinate of the point

Point2

public Point2(Point2 other)

Create a point with the same coordinates as other.

Parameters:

other - another point

Method Detail

getX

public double getX()

Returns the x-coordinate of this point.

Returns:

the x-coordinate of this point

getY

public double getY()

Returns the y-coordinate of this point.

Returns:

the y-coordinate of this point

setX

public void setX(double newX)

Sets the x-coordinate of this point to newX.

Parameters:

newX - the new x-coordinate of this point

setY

public void setY(double newY)

Sets the y-coordinate of this point to newY.

Parameters:

newY - the new y-coordinate of this point

set

public void set(double newX,
                double newY)

Sets the x-coordinate and y-coordinate of this point to newX and newY, respectively.

Parameters:

newX - the new x-coordinate of this point

newY - the new y-coordinate of this point

add

public Point2 add(Vector2 v)

Adds a vector to this point changing the coordinates of this point.

Mathematically, if this point is a and the vector is v then invoking this method is equivalent to computing a + v and assigning the value back to a.

Parameters:

v - a vector

Returns:

this Point2 object

subtract

public static Vector2 subtract(Point2 a,
                               Point2 b)

Returns a new Point2 equal to a - b.

Parameters:

a - a point

b - another point

Returns:

a new Point2 equal to a - b

toString

public java.lang.String toString()

Returns a string representation of this point. The string representation of this point is the x and y-coordinates of this point, separated by a comma and space, inside a pair of parentheses.

Overrides:

toString in class java.lang.Object

Returns:

a string representation of this point

See Also:

Object.toString()

hashCode

public int hashCode()

Returns a hash code for this point

Overrides:

hashCode in class java.lang.Object

Returns:

a hash code for this point

equals

public boolean equals(java.lang.Object obj)

Compares this point with the given object. The result is true if and only if the argument is not null and is a Point2 object having the same coordinates as this object.

Overrides:

equals in class java.lang.Object

Parameters:

obj - the object to compare this vector against

Returns:

true if the given object represents a Point2 equivalent to this point, false otherwise

similarTo

public boolean similarTo(Point2 other,
                         double tol)

Determines if two points are almost equal (similar). Two points are similar if the magnitude of their vector difference is smaller than the specified tolerance.

Parameters:

other - the other point to compare

tol - the threshold length of the vector difference (this - other)

Returns:

true if the length of (this - other) is less than tol, and false otherwise