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JavaScript Round

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The JavaScript Round function is one of the Math function and it is used to round the specified expression or an individual number to nearest integer.

The basic syntax of the round function in JavaScript Programming language is as shown below:

Math.round(number);

Number: It can be a number or a valid numerical expression.

  • If the number argument is positive or negative number, round() function will return the nearest value.
  • If the number argument is not a number, JavaScript round function will return NaN.
  • and, if the number argument is Null, JS round function will return Zero.

JavaScript Round Number Example

The Round function in JS is a mathematical function which returns the number to nearest integer. In this example, We are going to round the values of different data types and display the output

<!DOCTYPE html>
<html>
<head>
    <title> JavaScript ROUND Function </title>
</head>
<body>
  <h1> JavaScript ROUND Function </h1>
  <p id = "Pos"></p>
  <p id = "Neg"></p>
  <p id = "Dec"></p>
  <p id = "Dec1"></p>
  <p id = "Neg_Dec"></p>
  <p id = "Neg_Dec1"></p>
  <p id = "Str"></p>
  <p id = "Exp"></p>
  <p id = "Null"></p>
  <script>
    document.getElementById("Pos").innerHTML = Math.round(10);
    document.getElementById("Neg").innerHTML = Math.round(-10);
    document.getElementById("Dec").innerHTML = Math.round(14.05);
    document.getElementById("Dec1").innerHTML = Math.round(14.95);
    document.getElementById("Neg_Dec").innerHTML = Math.round(-6.05);
    document.getElementById("Neg_Dec1").innerHTML = Math.round(-6.95);
    document.getElementById("Str").innerHTML = Math.round("JavaScript");
    document.getElementById("Null").innerHTML = Math.round(null);
  </script>
</body>
</html>

ANALYSIS

  1. First two statements, We used the JS Round Function directly on both the Positive integer and negative integer.
  2. Next four statements, We used the Round() Function on both the Positive and negative Decimal values.
  3. Next statement, We tried JavaScript Round Function on String value. As we said before, this will return NaN (Not a Number) as output
  4. Last, We tried Round() Function on Null value and it return Zero as output

OUTPUT

JavaScript ROUND Function