Q Bignumber -> decimals?

[emichaf]

Is it possible to use ethers/bignumber with decimals?

[ricmoo]

BigNumber is only for integers.

You want the FixedNumber for decimal values, but for most purposes the utils.parseUnits and utils.formatUnits are nearly always enough for your purposes. :)

[emichaf]

How to do this in ethers.js? Using multipliers for precision?

const x = BigNumber.from(5) .div(BigNumber.from(10000)) .mul(BigNumber.from(3));

const y = BigNumber.from(3).mul(BigNumber.from(x));

Is it possible to change Bignumber lib in ethers.js ?

[zemse]

You can scale your numbers by 10¹⁸ by using the parseEther and formatEther, it makes life easy. This allows up to 18 decimal places, further that, underflow will take place.

const one = ethers.utils.parseEther('1'); // BigNumber:1e18

const x = one.mul(5).div(10000) .mul(3); // BigNumber:15e14
console.log(ethers.utils.formatEther(x)); // "0.0015"

const y = x.mul(3); // BigNumber:45e14
console.log(ethers.utils.formatEther(y)); // "0.0045"

If you want to use a different precision factor, then you can use the parseUnits and formatUnits.

[emichaf]

Thanks!