# Kotlin isFinite()

## Kotlin isFinite()

In Kotlin, the `isFinite()` function is used to check if a floating-point number is a finite value (neither infinite nor NaN).

This function is valuable for handling special cases in mathematical calculations where you want to ensure that the result is a valid finite number.

In this tutorial, we’ll explore the syntax of the `isFinite()` function and provide examples of its usage in Kotlin.

## Syntax

The syntax of the `isFinite()` function is:

``fun Double.isFinite(): Boolean``

The `isFinite()` function is an extension function for double-precision floating-point numbers and returns `true` if the number is a finite value, and `false` otherwise.

## Examples for isFinite() function

### 1. Using isFinite() to Check for Finite Values

In this example, we’ll use `isFinite()` to check if a result from a mathematical operation is a finite value.

Kotlin Program

``````fun main() {
val result1 = 10.0 / 5          //2
val result2 = 10.0 / 0          //Infinity
val result3 = Math.sqrt(-1.0)   //NaN

println("result1 : \$result1")
println("result2 : \$result2")
println("result3 : \$result3")

println("Is result1 finite? \${result1.isFinite()}")
println("Is result2 finite? \${result2.isFinite()}")
println("Is result3 finite? \${result3.isFinite()}")
}``````

Output

``````result1 : 2.0
result2 : Infinity
result3 : NaN
Is result1 finite? true
Is result2 finite? false
Is result3 finite? false``````

In this example, we perform mathematical operations that result in finite value (division by a non-zero number), an infinite value (division by zero), and NaN (Math.sqrt()).

The `isFinite()` function is used to check if the results are finite, and the outcome is printed.

## Summary

In this tutorial, we’ve covered the `isFinite()` function in Kotlin, its syntax, and how to use it for checking if a double-precision floating-point number is a finite value.