Warning: session_start() [function.session-start]: open(/tmp/sess_h3shfslgghmf2hecn8fpfn6or7, O_RDWR) failed: Disk quota exceeded (122) in /home/vipozico/forum.tutorials7.com/qa-include/qa-app-users.php on line 143
Round numbers to specific precision in JavaScript
settingsAccountsettings
By using our mini forum, you acknowledge that you have read and understand our Cookie Policy and Privacy Policy
Menusettings

Q: Round numbers to specific precision in JavaScript

+2 votes

Write a JS function (program/code) that rounds numbers to specific precision.

The input comes as an array of two numbers:

  • The first value is the number to be rounded;
  • The second is the precision (significant decimal places)

If a precision is passed, that is more than 15 it should automatically be reduced to 15.

Examples:

Input:
[3.1415926535897932384626433832795, 2]

Output:
3.14


Input:
[10.5, 3]

Output:
10.5

The output should be printed to the console. Do not print insignificant decimals.

asked in JavaScript category by user eiorgert

1 Answer

+1 vote

Here is the solution of rounding the numbers in JavaScript:

function round(arr) {
    let [num,precision]=arr;//if you know how many element are in the array - you can assign them this way
    if (precision > 15) {
        precision = 15;
    }
    let denominator = Math.pow(10, precision);
    console.log(Math.round(num * denominator) / denominator);
    //or use this code: console.log(Number(num.toFixed(precision)));
}

round([10.5, 3]);

 

answered by user mitko
...