使用 BigNumber 处理舍入问题

Question

I am trying to subtract two numbers with more decimals. But it is rounding up. How can I use BigNumber to make sure the numbers are not rounded and the calculation is precise.

 const myObj = { total: 5000000, filled: 4999999.9999999996870756 }; const total = new BigNumber(myObj.total); const filled = new BigNumber(myObj.filled); const remaining = total.minus(filled); console.log(total, filled, remaining); if(remaining === 0.0000000003129244) console.log("remaining calculation is correct") else console.log("incorrect calculation")

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Answer 1

first you need to define string variables to not rounding it up. after that for comparing values of bigNumber it's better to use ' comparedTo ' refer to documents

 const myObj = { total: '5000000', filled: '4999999.9999999996870756' }; const total = new BigNumber(myObj.total); const filled = new BigNumber(myObj.filled); const remaining = total.minus(filled); console.log('total',total); console.log('filled',filled); console.log('remaining', remaining); if(remaining.comparedTo(0.0000000003129244) === 0) console.log("remaining calculation is correct") else console.log("incorrect calculation")

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