StrictMath atan() Method in Java

The java.lang.StrictMath.atan() is an inbuilt method of StrictMath class which is used to return the tangent of a given argument. It returns the angle is within the range of -pi/2 and pi/2. It gives rise to two special results:

• The output is NaN if the passed parameter is a NaN.
• If the passed argument is 0, then the result is also a 0 retaining the same sign as the argument.

Syntax :

public static double atan(double num)

Parameters: The method accepts one parameter num of double type and refers to the value whose tangent is to be returned.

Return Value: The method returns the arc tangent value of the argument.

Examples :

Input: num = 0.61
Output: 0.5477400137159024

Input: num = 0.0
Output: 0.0

Input: num = -71.0
Output: -1.5567127509720364

Below programs illustrate the java.lang.StrictMath.atan() method:
Program 1:

java

// Java program to illustrate the
// java.lang.StrictMath.atan()
import java.lang.*;

public class Geeks {

    public static void main(String[] args)
    {

        double num1 = 0.70, num2 = 55.00, num3 = 0;

        double atanValue = StrictMath.atan(num1);
        System.out.println("The arc tangent of " +
                         num1 + " = " + atanValue);

        atanValue = StrictMath.atan(num2);
        System.out.println("The arc tangent of " +
                         num2 + " = " + atanValue);

        atanValue = StrictMath.atan(num3);
        System.out.println("The arc tangent of " +
                          num3 + " = " + atanValue);
    }
}

Output:

The arc tangent of 0.7 = 0.6107259643892086
The arc tangent of 55.0 = 1.5526165117219184
The arc tangent of 0.0 = 0.0

Program 2:

java

// Java program to illustrate the
// java.lang.StrictMath.atan()
import java.lang.*;

public class Geeks {

    public static void main(String[] args)
    {

        double num1 = -0.52, num2 = -71.00, num3 = 0;

        double atanValue = StrictMath.atan(num1);
        System.out.println("The arc tangent of " +
                           num1 + " = " + atanValue);

        atanValue = StrictMath.atan(num2);
        System.out.println("The arc tangent of " +
                            num2 + " = " + atanValue);

        atanValue = StrictMath.atan(num3);
        System.out.println("The arc tangent of " +
                            num3 + " = " + atanValue);
    }
}

Output:

The arc tangent of -0.52 = -0.4795192919925962
The arc tangent of -71.0 = -1.5567127509720364
The arc tangent of 0.0 = 0.0