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() methodimport 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
