递归在PHP中的应用举例
<?php //amortizationTable表示还贷计算函数 function amortizationTable($pNum, $periodicPayment, $balance, $monthlyInterest) { //计算支付利息 $paymentInterest = round ($balance*$monthlyInterest, 2); //计算还款额 $paymentPrincipal = round($periodicPayment - $paymentInterest,2); //用余额减去还款额 $newBalance = round($balance-$paymentPrincipal,2); //如果余额<每月还款,设置为0 if ($newBalance < $paymentPrincipal){ $newBalance = 0; } printf ("<tr><td>%d</td>",$pNum); printf ("<td>$%s</td>", number_format ($newBalance,2)); printf ("<td>$%s</td>", number_format ($periodicPayment,2)); printf ("<td>$%s</td>", number_format ($paymentPrincipal,2)); printf ("<td>$%s</td></tr>", number_format ($paymentInterest,2)); #if balance not yet zero, recursively call amortizationTable() if ($newBalance>0){ $pNum++; amortizationTable($pNum, $periodicPayment, $newBalance, $monthlyInterest); }else{ return 0; } } $balance = 10000.00; // 贷款余额 $interestRate = 0.0575; //贷款利率 $monthlyInterest = $interestRate/12; //每月利率 $termLength = 5; //贷款期限,单位为年 $paymentsPerYear = 12; //每年支付次数 $paymentNumber = 1; //付款迭代 $totalPayments = $termLength*$paymentsPerYear; //确定付款次数 $intCalc = 1 + $interestRate / $paymentsPerYear; //确定分期付款的利息部分 $periodicPayment = $balance * pow($intCalc, $totalPayments)*($intCalc -1)/(pow($intCalc,$totalPayments) -1); //每月还款额限制到小数点后两位 $periodcPayment = round($periodicPayment,2); //创建表 echo "<table width='50%' align = 'center' border = '1'>"; echo "<tr> <th>Payment Number</th><th>Balance</th> <th>payment</th><th>Principal</th><th>Interest</th> </tr>"; //创建递归函数 amortizationTable ($paymentNumber, $periodcPayment, $balance,$monthlyInterest); //关闭表 echo "</table>"; ?>