Pi (π) is a well-known mathematical constant whose value is 22/7 or 3.14159265359. Programming languages also use this constant for mathematical calculation.
Here we discuss PI with respect to the Java programming language.
In Java PI is defined as a field in java.lang.Math class.
It is defined as
static double PI
and described as
The
https://docs.oracle.com/doublevalue that is closer than any other to pi, the ratio of the circumference of a circle to its diameter.
How to use PI in Java
PI is a static constant in Math class, so to access it we use the class name. PI. It can also be accessed using objects.
Math.PI
1 2 3 4 5 6 | public class MyClass { public static void main(String args[]) { System.out.println("Value of PI = " + Math.PI); } } |
1 | Value of PI = 3.141592653589793 |
Java Program to calculate Area of Circle using Math.PI
Write a Java Program to calculate the Area of Circle
Below is the simple program to calculate the area of the Circle.
Program reads the value of radius using scanner method and stored in variable r.
Area is calculated using formula
area=Math.PI*r*r;
1 2 3 4 5 6 7 8 9 10 11 | import java.util.Scanner; public class MyClass { public static void main(String args[]) { int r; Scanner sc=new Scanner(System.in); r=sc.nextInt(); double area=Math.PI*r*r; System.out.println("Area of Circle is = " + area); } } |
1 | Area of Circle is = 314.1592653589793 |
Write a Java program to calculate circumference of a Circle
1 2 3 4 5 6 7 8 9 10 11 12 | import java.util.Scanner; public class MyClass { public static void main(String args[]) { int r; Scanner sc=new Scanner(System.in); r=sc.nextInt(); double circumference=2*Math.PI*r; System.out.println("Circumference of Circle is = " + circumference); } } |
1 | Circumference of Circle is = 62.83185307179586 |
The scanner class is used to read the values from user.
How to print PI (π) symbol in Java
1 2 3 4 5 6 7 8 9 | import java.util.Scanner; public class MyClass { public static void main(String args[]) { System.out.println("PI Symbol is \u03c0 "); System.out.println("PI Symbol is π "); } } |
1 2 | PI Symbol is π PI Symbol is π |
How to write pi in java
You can write Pi by using Unicode value ‘\u03c0’ or by using the string constant “π”.
1 2 | System.out.println("PI Symbol is \u03c0 "); System.out.println("PI Symbol is π "); |
How to use Math.PI in java
to use Math.pi Just use Math.PI as below
1 2 3 4 5 | public class MyClass { public static void main(String args[]) { System.out.println("Value of PI = " + Math.PI); } } |