Java Math.PI is a public static constant in Math class. PI constant is high-precision approximation (3.141592653589793) and usable in any Java code.
Java Math.PI
Example 1: Print PI number using Math.PI constant.
System.out.println(Math.PI); //3.141592653589793
Example 2: Find the area and perimeter of a circle for a given radius (as user input)
Scanner input = new Scanner(System.in); System.out.print("ınput a value for radius > "); double radius = input.nextDouble(); double perimeter = 2 * Math.PI * radius; double area = Math.PI * radius * radius; System.out.println("Perimeter of the cicle is: " + perimeter); System.out.println("Area of the cicle is: " + area);
Console Output:
input a value for radius > 15 Perimeter of the cicle is: 94.24777960769379 Area of the cicle is: 706.8583470577034