JavaScript: Round a number to a given specific decimal places
JavaScript Math: Exercise-14 with Solution
Write a JavaScript function to round a number to decimal place.
Test Data:
console.log(precise_round(12.375,2));
console.log(precise_round(12.37499,2));
console.log(precise_round(-10.3079499, 3));
Output :
"12.38"
"12.37"
"-10.308"
Pictorial Presentation:
Sample Solution:
HTML Code:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Round a number to a given decimal places</title>
</head>
<body>
</body>
</html>
JavaScript Code:
//Ref.https://bit.ly/3zxAhnH
function precise_round(n, r) {
let int = Math.floor(n).toString()
if (typeof n !== 'number' || typeof r !== 'number') return 'Not a Number'
if (int[0] == '-' || int[0] == '+') int = int.slice(int[1], int.length)
return n.toPrecision(int.length + r)
}
console.log(precise_round(12.375,2));
console.log(precise_round(-10.3079499, 3));
console.log(precise_round(10.49999,0));
console.log(precise_round(10.49999,2));
Sample Output:
12.38 -10.308 10 10.50
Flowchart:

Live Demo :
See the Pen javascript-math-exercise-14 by w3resource (@w3resource) on CodePen.
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