TypeScript Math round()

In this chapter, we will explore the Math.round() method in TypeScript. This method rounds a number to the nearest integer. Understanding how to use Math.round() is useful for rounding numbers to the nearest whole number.

Table of Contents

1. Definition
2. Syntax
3. Examples
4. Conclusion

1. Definition

The Math.round() method rounds a number to the nearest integer. If the fractional part of the number is 0.5 or greater, the argument is rounded to the next higher integer. If the fractional part is less than 0.5, the argument is rounded to the next lower integer.

2. Syntax

Math.round(x);

Parameters

• x: A number to be rounded.

Return Value

The method returns the value of the number rounded to the nearest integer.

3. Examples

Let's look at some examples to understand how Math.round() works in TypeScript.

Example 1: Basic Usage

In this example, we use Math.round() to round a positive decimal number to the nearest integer.

let num: number = 4.7;
let result = Math.round(num);
console.log(result); // Output: 5

Example 2: Rounding a Negative Decimal Number

In this example, we use Math.round() to round a negative decimal number to the nearest integer.

let num: number = -4.7;
let result = Math.round(num);
console.log(result); // Output: -5

Example 3: Rounding a Number with .5 Fractional Part

In this example, we use Math.round() to round a number with a fractional part of 0.5.

let num1: number = 4.5;
let num2: number = -4.5;
console.log(Math.round(num1)); // Output: 5
console.log(Math.round(num2)); // Output: -4

Example 4: Rounding Whole Numbers

In this example, we use Math.round() to round whole numbers. Whole numbers remain unchanged.

let num1: number = 5;
let num2: number = -5;
console.log(Math.round(num1)); // Output: 5
console.log(Math.round(num2)); // Output: -5

Example 5: Using Math.round() with Expressions

In this example, we use Math.round() with expressions to round the result to the nearest integer.

let num1: number = 3.7;
let num2: number = 2.2;
let result = Math.round(num1 + num2);
console.log(result); // Output: 6

Example 6: Rounding Small Positive Decimal Numbers

In this example, we use Math.round() to round small positive decimal numbers to the nearest integer.

let num: number = 0.1;
let result = Math.round(num);
console.log(result); // Output: 0

Example 7: Rounding Small Negative Decimal Numbers

In this example, we use Math.round() to round small negative decimal numbers to the nearest integer.

let num: number = -0.1;
let result = Math.round(num);
console.log(result); // Output: 0

4. Conclusion

In this chapter, we explored the Math.round() method in TypeScript, which is used to round a number to the nearest integer. We covered its definition, syntax, parameters, return value, and provided several examples to demonstrate its usage. Understanding how to use Math.round() effectively can help in various mathematical calculations and scenarios where rounding numbers to the nearest whole number is required.