JavaScript Math.log1p()
Syntax & Examples

Math.log1p() static-method

The Math.log1p() method in JavaScript returns the natural logarithm (㏒e, also known as ㏑) of 1 plus a given number (x). This is particularly useful for values of x close to zero, where using Math.log(1 + x) might result in a loss of precision. It is a static method of Math, meaning it is always used as Math.log1p() and not as a method of a Math object created (Math is not a constructor).

Syntax of Math.log1p()

The syntax of Math.log1p() static-method is:

Math.log1p(x)

This log1p() static-method of Math returns the natural logarithm (㏒e; also ㏑) of 1 + x for the number x.

Parameters

ParameterOptional/RequiredDescription
xrequiredA number for which to return the natural logarithm of 1 plus the number.

Return Type

Math.log1p() returns value of type Number.


✐ Examples

1 Using Math.log1p() with a positive number

In this example, we use the Math.log1p() method to find the natural logarithm of 1 plus 10.

For example,

  1. We call Math.log1p() with 10 as the argument.
  2. The method returns the natural logarithm of 11.
  3. We log the result to the console using console.log().

JavaScript Program

console.log(Math.log1p(10));

Output

2.3978952727983707

2 Using Math.log1p() with zero

In this example, we use the Math.log1p() method to find the natural logarithm of 1 plus 0.

For example,

  1. We call Math.log1p() with 0 as the argument.
  2. The method returns the natural logarithm of 1, which is 0.
  3. We log the result to the console using console.log().

JavaScript Program

console.log(Math.log1p(0));

Output

0

3 Using Math.log1p() with a negative number

In this example, we use the Math.log1p() method to find the natural logarithm of 1 plus -0.5.

For example,

  1. We call Math.log1p() with -0.5 as the argument.
  2. The method returns the natural logarithm of 0.5.
  3. We log the result to the console using console.log().

JavaScript Program

console.log(Math.log1p(-0.5));

Output

-0.6931471805599453

Summary

In this JavaScript tutorial, we learned about log1p() static-method of Math: the syntax and few working examples with output and detailed explanation for each example.