PHP房貸計算器代碼，等額本息，等額本金

    debx();  
      
    function debx()  
    {  
        $dkm     = 240; //貸款月數，20年就是240個月  
        $dkTotal = 10000; //貸款總額  
        $dknl    = 0.0515;  //貸款年利率  
        $emTotal = $dkTotal * $dknl / 12 * pow(1 + $dknl / 12, $dkm) / (pow(1 + $dknl / 12, $dkm) - 1); //每月還款金額  
        $lxTotal = 0; //總利息  
        for ($i = 0; $i < $dkm; $i++) {  
            $lx      = $dkTotal * $dknl / 12;   //每月還款利息  
            $em      = $emTotal - $lx;  //每月還款本金  
            echo "第" . ($i + 1) . "期", " 本金:", $em, " 利息:" . $lx, " 總額:" . $emTotal, "<br />";  
            $dkTotal = $dkTotal - $em;  
            $lxTotal = $lxTotal + $lx;  
        }  
        echo "總利息:" . $lxTotal;  
    }  
      
      
    function debj()  
    {  
        $dkm     = 240; //貸款月數，20年就是240個月  
        $dkTotal = 10000; //貸款總額  
        $dknl    = 0.0515;  //貸款年利率  
           
        $em      = $dkTotal / $dkm; //每個月還款本金  
        $lxTotal = 0; //總利息  
        for ($i = 0; $i < $dkm; $i++) {  
            $lx      = $dkTotal * $dknl / 12; //每月還款利息  
            echo "第" . ($i + 1) . "期", " 本金:", $em, " 利息:" . $lx, " 總額:" . ($em + $lx), "<br />";  
            $dkTotal -= $em;  
            $lxTotal = $lxTotal + $lx;  
        }  
        echo "總利息:" . $lxTotal;  
    }  
      
      
    exit;