使用 BigNumber 處理舍入問題

Question

我正在嘗試用更多小數減去兩個數字。 但它正在四舍五入。 如何使用 BigNumber 確保數字不四舍五入且計算准確。

 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

首先，您需要定義字符串變量以不四舍五入。 之后為了比較bigNumber 的值，最好使用“ compareTo ”參考文檔

 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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