start . me .
Directory path . web , js .

File : js-fixed-trunc.txt

        dario@win11 MINGW64 ~
$ node
Welcome to Node.js v20.13.1.
Type ".help" for more information.
> function truncate(number,decimals_count){ number *= 10**decimals_count; number = Math.trunc( number ); number /= 10**decimals_count; return number; }
undefined
> Math.round(3.149)
3
> Math.trunc(3.149)
3
> (3.149).toFixed(2)
'3.15'
> truncate(3.149,2).toString()
'3.14'
> function round(number,decimals_count){ number *= 10**decimals_count; number = Math.round( number ); number /= 10**decimals_count; return number; }
undefined
> round(3.149,2).toString()
'3.15'
>