Question

我正在使用一个计算器来计算单利和复利。很好，仅凭简单的兴趣，但我似乎无法使用循环来解决复利问题。我需要一个循环，因为将数据推入数组以供以后在图表中使用。

我从这里得到公式：https://www.moneysmart.gov.au/managing-your-money/saving/compound-interest

我将其用作参考：https://www.bankrate.com/calculators/retirement/roi-calculator.aspx

代码在这里起作用：http://www.course0001.com/fiverr/iddqd 到目前为止，我有这个（更新）：


// Inputs from user:

// Initial deposit (starting balance)
// Number of years
// Interest
// Frequent Deposit amount
// Deposit and compound frequency (monthly, weekly, yearly)

// Calculations
var investedCapitalArray = [];
var simpleInterestArray = [];
var compoundInterestArray = [];
var compoundPrincipal = 0;
var years = [];
var accumulatedInvestment;

function calculate() {
    years = [];
    let interest = rateNumeric.getNumber() / 100; // annual interest rate
    let additionalDeposit = additionalNumeric.getNumber(); // Regular deposit
    let frequency = freqInput.value; // Frequency of regular deposit
    let initialDeposit = initialNumeric.getNumber();
    let taxRate = taxNumeric.getNumber();

    // Invested captal amount first year
    investedCapitalArray = [];
    investedCapitalArray.push(initialDeposit + (frequency * additionalDeposit));

    // simple interest first year
    simpleInterestArray = [];
    simpleInterestArray.push((investedCapitalArray[0]  * ( (interest) / 100)) * (1 - taxRate));

    // compund interest first year
    compoundInterestArray = [];
    let firstYearInvestment = investedCapitalArray[0]; // First deposit + regular deposits in first year

    for (let i = 1 ; i < yearsInput.value ; i++) {
        // Invested capital over the years (correct results)
        investedCapitalArray.push( (investedCapitalArray[i-1]) +
            (frequency * additionalDeposit) );

        // simple interest over the years (correct results)
        simpleInterestArray.push( simpleInterestArray[i-1] +
            ((firstYearInvestment + 
            ((frequency) * additionalDeposit) * i ) * interest) );

        // compound interest over the years (incorrect results)  
        compoundInterestArray.push( investedCapitalArray[i-1] * 
            Math.pow(1 + interest / 100, i) -  initialDeposit);

        years.push('Year' +i);
    }
}

Answer 1

问题在于您应该使用(investedCapitalArray[i - 1] + compoundInterestArray[i - 1]) * (1 + 0.07)的括号。谢谢

Answer 2

我认为问题出在将对象拆箱。试试这个：

compoundInterestArray.push( compoundInterestArray[i-1] + (parseInt(investedCapitalArray[i-1]) + parseInt(simpleInterestArray[i-1])) * ( rateNumberic.getNumber() / 100))  );

Answer 3

感谢大家的投入，在深入研究复利主题之后，我编写了一种效果很好的算法。实际上很简单。

我的算法基于以下解释： “什么是复利？复利（或复利）是根据初始本金计算的利息，还包括存款或贷款以前各期的所有累计利息。”

因此它像这样在循环中工作：

compoundInterest + =（（（（simpleInterestArray [i-1] + compoundInterest）*（兴趣））;

下面的完整代码。


    for (let i = 1; i < yearsInput.value; i++) {

        // Invested capital over the years (works fine)
        investedCapital = (investedCapitalArray[i - 1]) +
            (frequency * additionalDeposit);
        investedCapitalArray.push(investedCapital);

        //  imple interest over the years (works fine)
        simpleInterest = simpleInterestArray[i - 1] +
            ((firstYearInvestment + (frequency * additionalDeposit) * i) * interest);
        simpleInterestArray.push(simpleInterest);

        // compound interest over the years (correct results)
        compoundInterest += (((simpleInterestArray[i - 1] + compoundInterest) * (interest)));
        compoundInterestArray.push(compoundInterest);
    }

JavaScript循环中的复利计算器

3 个答案: