How to round number to nearest scale/factor number

Question

Sorry about the title, it a little bit hard to explain this question in a title.

So I want to round a number to its nearest scale/factor(always up) or how this is called when its added in a text field. I want to do this with javascript but coul d not find a function or example for this, but I hope that there is a function for this solution?

Example:

Scale/factor = 12

User enters the number 3 , the number should change into 12
User enters the number 25, the number should change into 36
User enters the number 47, the number should change into 48

Possible duplicate of [Javascript: Round up to the next multiple of 5](https://stackoverflow.com/questions/18953384/javascript-round-up-to-the-next-multiple-of-5) — CBroe, Jun 28 '18 at 09:36

score 1 · Accepted Answer · answered Jun 28 '18 at 09:33

1

Just round up with Math.ceil the result of dividing and multiply it with your factor:

const factor = 12;
Math.ceil(47 / factor) * factor; // 48
Math.ceil(25 / factor) * factor; // 36

answered Jun 28 '18 at 09:33

hsz

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score 0 · Answer 2 · answered Jun 28 '18 at 09:35

It looks like you want a higher-order function that uses Math.ceil:

const makeTransform = scale => num => Math.ceil(num / scale) * scale;
const transform12 = makeTransform(12);
console.log(transform12(3));
console.log(transform12(25));
console.log(transform12(47));

score 0 · Answer 3 · answered Jul 10 '18 at 16:07

Here is a solution without involving floats:

function stickTo (factor, num) {
    const rest = num % factor;
    if (rest) {
        return num + factor - rest;
    }
    return num
}

// stickTo(12, 3) --> 12
// stickTo(12, 25) --> 36
// stickTo(12, 47) --> 48
// stickTo(12, 12) --> 12

How to round number to nearest scale/factor number

3 Answers3