Catch-22 calculating in PHP

[JasonGreen]

There doesn't seem to be a way around this. I want to be able to calculate values using variables but in such a way that the value continues to change - however, I cannot simply write out the number, I need a variable.

 

Here is the problem, look at my example below, if I were to use calculations based on define variable, I would end up using longer and longer calculations and that would be a horible mess.

 

Like this

 

print $serveryear . "      " . $servercost . "              " . ($servercost * HIGH_DEPREC) . "            " . ($servercost - $servercost * HIGH_DEPREC) . "\n";

print ($serveryear + 1) . "      " . ($servercost - $dodgecost * HIGH_DEPREC) . "      " . ($servercost - $servercost * HIGH_DEPREC * HIGH_DEPREC) . "      " . ETC . "\n";

It just grows and grows!!!!

 

At the same time I cannot define a variable for each and every calculation, that too is a mess that grows and grows.

 

DELL SERVER– Depreciation over 5-year period (Factor:  .20)

 

YEAR        Start Value      Deprec      Ending Value

 

2004          21297.00        4259.40    17037.60

 

2005          17037.60        3407.52    13630.08

2006

2007

2008

 

Any insights, comments, and suggestions will be greatly appreaciated.

 

Thanks

[Calver]

Jason,

 

I think you need to use a function, something like this, then you can pass any values to it:

 

<?php

ShowDep("DELL SERVER", 21297, 2004, 5, 20);

function ShowDep($title, $servercost, $serveryear, $numYears, $depRate){
    $startValue = $servercost;
    $depValue = 0;
    $endValue = 0;
    print $title . "<br/>";
    for ( $counter = 0; $counter < $numYears; $counter += 1) {
        $depValue = $startValue * $depRate / 100;
        $endValue = $startValue - $depValue;
        print $serveryear + $counter . " --- " .
              $startValue  . " --- " .
              $depValue  . " --- " .
              $endValue  . "<br/>";
        $startValue = $endValue;
    }
}

?>

 

I've only just started to learn PHP, so there's probably a better way to do it. Also, the output is untidy as I've not figured out the print statement yet!