Scale a number to a given range in javascript

Asked May 15 '22 at 18:17

Active Jun 04 '22 at 14:53

Viewed 73 times

-1

How to create a function to scale numbers when the range is in the center.

Let's say 300 is the center position between 0 and 600. How do you calculate if the range is less than 0 the return should have 0.2 and when the range is greater than 600 the return should have 0.2 as well however if the range is 300 the return should have 1.2

let range = 300;
let max_range = 600;

const getScaleNumber = (range, max_range) => {
   return (range / max_range) * 2.4;
}

The given formula returns a 1.2 number which is what I expected if the range is in the center of 0 and 600 however if I did the 0(range) / 600 * 2.4 it returns 0, and it should return 0.2 if the range is less than 0 or greater than 600

How to create a function that increases and decreases a return number with a minimum return of 0.2 and a maximum return of 1.2.

edited Jun 04 '22 at 14:53

asked May 15 '22 at 18:17

Vince

2

what is actual the question? what have you tried? please add a list of values and wanted result. – Nina Scholz May 15 '22 at 18:23
alert((300 / 600) * 2.4); – LDS May 15 '22 at 18:26
(300/600) should be in bracket – LDS May 15 '22 at 18:27
2

@LDS, no brackets required for same type of operation. – Nina Scholz May 15 '22 at 18:27
That's [math](https://math.stackexchange.com), not programming. Programming starts when you're able to solve the problem with pen and paper, e.g. https://math.stackexchange.com/questions/425126/map-values-090-to-20 – jabaa May 15 '22 at 19:07
1

`1.2 - Math.abs(x - 300)/300` – lemon May 15 '22 at 20:50
Hey @lemon, What if the center is 600 and the min_range is 300 and the max_range is 900. When the range is on 600 it should return 1.2 – Vince May 15 '22 at 23:03
1

300-600-900 is a shift of +300 from 0-300-600, so you just need to subtract 300 more from your x (`1.2 - Math.abs(x - 600)/300`) – lemon May 15 '22 at 23:05
1

you can generalize it with `1.2 - Math.abs(x - )/` – lemon May 15 '22 at 23:09
1

niceeee It actually solves the problem tho :) – Vince May 15 '22 at 23:16
1

you can try with `min(max( out, ), – lemon May 16 '22 at 09:54
Hey @lemon, Why does 1 - Math.abs(0 - 300)/300 is not returning 0 number – Vince May 16 '22 at 17:56
Let us [continue this discussion in chat](https://chat.stackoverflow.com/rooms/244784/discussion-between-lemon-and-vince). – lemon May 16 '22 at 18:10

Scale a number to a given range in javascript

0 Answers0