Java Math log() method with example

The java.lang.Math.log() method returns the natural logarithm (base e) of a double value as a parameter. There are various cases :

If the argument is NaN or less than zero, then the result is NaN.
If the argument is positive infinity, then the result is positive infinity.
If the argument is positive zero or negative zero, then the result is negative infinity.

Syntax :

public static double log(double a)

Parameter :

a : User input

Return Type:

This method returns the value ln a.

Example 1: To show the working of java.lang.Math.log() method.

java

// Java program to demonstrate working
// of java.lang.Math.log() method

import java.lang.Math;

class GFG {

    // driver code
    public static void main(String args[])
    {
        double a = -2.55;
        double b = 1.0 / 0;
        double c = 0, d = 145.256;

        // negative integer as argument, output NAN
        System.out.println(Math.log(a));

        // positive infinity as argument, output Infinity
        System.out.println(Math.log(b));

        // positive zero as argument, output -Infinity
        System.out.println(Math.log(c));

        // positive double as argument
        System.out.println(Math.log(d));
    }
}

Output:

NaN
Infinity
-Infinity
4.978497702968366

Example 2:

Java

import java.io.*;

class GFG {
    public static void main(String[] args)
    {
        double number = 10.0;
        double result = Math.log(number);
        System.out.println(result);
    }
}

Output

2.302585092994046

Java Math log() method with example

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