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" double value whose natural logarithm is to be calculated.
- Return Type: Returns a double value representing ln(a) (natural logarithm of a).
Example 1: This program demonstrates how the Math.log() method behaves for different types of input values in Java.
OutputNaN
Infinity
-Infinity
4.978497702968366
Explanation:
- Math.log(a) returns NaN because the logarithm of a negative number is undefined.
- Math.log(b) returns Infinity since the input value is positive infinity.
- Math.log(c) returns -Infinity because the logarithm of zero tends toward negative infinity.
- Math.log(d) returns the natural logarithm (base e) of a positive number.
Example 2: This program shows how to compute the natural logarithm (base e) of a number using the Math.log() method in Java.
