Cartesian to Polar & Polar to Cartesian Coordinate

Cartesian / Rectangular to Polar Conversion

The java code converts the Cartesian coordinate values (x,y) into polar coordinate values (r,Θ).

The input values for x and y are read from the user using scanner object and these values are converted into corresponding polar coordinate values by following two equations.

Polar Coordinate radius

Polar Coordinate theta

import java.util.Scanner;

public class Cartesian2Polar {

 public static void main(String[] args) 
 {
  
       System.out.println("\nCartesian to Polar Conversion"); 
       Scanner sc = new Scanner(System.in);
       
       System.out.println("\n Enter x-axis value : ");
       int x =sc.nextInt();
       System.out.println("\n Enter y-axis value : ");
       int y =sc.nextInt();
       
       
       double radius =  Math.sqrt( Math.pow(x, 2) + Math.pow(y, 2) );        
       double radiant = Math.atan(y/x);
       double angle = radiant * (180/Math.PI);
       
       System.out.println("Radius :"  + radius);
       System.out.println("Angle in radiant: "  + radiant);
       System.out.println("Angle in degree: "  + angle);
 }

}

Output

Cartesian to Polar Conversion

Enter x-axis value : 
3
Enter y-axis value : 
3

Radius :4.242640687119285
Angle in radiant:0.7853981633974483
Angle in degree:45.0

Polar to Cartesian/Rectangular Conversion

The Java code converts the polar coordinate values (r,Θ) into Cartesian coordinate values (x,y).


The input values for r and Θ are read from the user using scanner object and these values are converted into corresponding Cartesian/rectangular coordinate values by following two equations.

Cartesian x-axis

Cartesian y-axis

import java.util.Scanner;

public class Polar2Cartesian {

 public static void main(String[] args) 
 {
  
      System.out.println("\nPolar to Cartesian Conversion"); 
      Scanner sc = new Scanner(System.in);
              
      System.out.println("\nEnter radius value : ");
      double radius =sc.nextDouble();
      System.out.println("\nEnter angle in degree : ");
      double angle =sc.nextDouble();
      
      double radiant = angle * (Math.PI/180);
      
      double x = radius * Math.cos(radiant);
      double y = radius * Math.sin(radiant);
      
      System.out.println("\nx  :"  + x);
      System.out.println("y  : "  + y);
      
      
 }

}

Output

Polar to Cartesian Conversion

Enter radius value : 
12
Enter angle in degree : 
195

x  :-11.59110991546882
y  : -3.1058285412302498