You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
80 lines
2.4 KiB
Java
80 lines
2.4 KiB
Java
/*This is a Java Program to find the area of a polygon using slicker method. The algorithm assumes the usual mathematical convention that positive y points upwards. In computer systems where positive y is downwards (most of them) the easiest thing to do is list the vertices counter-clockwise using the “positive y down” coordinates. The two effects then cancel out to produce a positive area.*/
|
|
|
|
//This is a java program to find the area of polygon using Slicker algorithm
|
|
import java.util.*;
|
|
|
|
class Area_polygon_Slicker
|
|
{
|
|
static final int MAXPOLY = 200;
|
|
static final double EPSILON = 0.000001;
|
|
|
|
static class Point
|
|
{
|
|
double x, y;
|
|
}
|
|
|
|
static class Polygon
|
|
{
|
|
Point p[] = new Point[MAXPOLY];
|
|
int n;
|
|
|
|
Polygon()
|
|
{
|
|
for (int i = 0; i < MAXPOLY; i++)
|
|
p[i] = new Point();
|
|
}
|
|
}
|
|
|
|
static double area(Polygon p)
|
|
{
|
|
double total = 0;
|
|
for (int i = 0; i < p.n; i++)
|
|
{
|
|
int j = (i + 1) % p.n;
|
|
total += (p.p[i].x * p.p[j].y) - (p.p[j].x * p.p[i].y);
|
|
}
|
|
return total / 2;
|
|
}
|
|
|
|
static public void main(String[] args)
|
|
{
|
|
Polygon p = new Polygon();
|
|
Scanner sc = new Scanner(System.in);
|
|
System.out.println("Enter the number of points in Polygon: ");
|
|
p.n = sc.nextInt();
|
|
System.out.println("Enter the coordinates of each point: <x> <y>");
|
|
for (int i = 0; i < p.n; i++)
|
|
{
|
|
p.p[i].x = sc.nextDouble();
|
|
p.p[i].y = sc.nextDouble();
|
|
}
|
|
double area = area(p);
|
|
if (area > 0)
|
|
System.out.print("The Area of Polygon with " + p.n
|
|
+ " points using Slicker Algorithm is : " + area);
|
|
else
|
|
System.out.print("The Area of Polygon with " + p.n
|
|
+ " points using Slicker Algorithm is : " + (area * -1));
|
|
sc.close();
|
|
}
|
|
}
|
|
|
|
/*
|
|
Enter the number of points in Polygon:
|
|
4
|
|
Enter the coordinates of each point: <x> <y>
|
|
1 1
|
|
1 6
|
|
6 6
|
|
6 1
|
|
The Area of Polygon with 4 points using Slicker Algorithm is : 25.0
|
|
|
|
Enter the number of points in Polygon:
|
|
5
|
|
Enter the coordinates of each point: <x> <y>
|
|
1 2
|
|
4 5
|
|
9 8
|
|
3 2
|
|
1 5
|
|
The Area of Polygon with 5points using Slicker Algorithm is : 6.0 |