HELP! converting repetitive calculation code into a function

[martincrumlish]

Hi,

I am writing a betting calculation script. This will involve multiple combinations of odds and stakes etc which are entered via a form.

A user selects which type of bet they want and when they clickm submit the calculation for this script is run. i.e: a single bet is: odds * stake + stake = return1

a double bet is:
odds stake + stake = return1
odds1 return1 + return1 = return

There are some advanced betting selections that have 8 selections and involve a number of combinations of the different selections. What I need is a function which i can pass these values through to get a result.

Here is an example of the calculation I have for a double bet:

if($calc == "Double")
	{
	if($rf1){$odds1 = $odds1 * (1 - $rf1);}
	if($rf2){$odds2 = $odds2 * (1 - $rf2);}
	$total1 = $odds1/$odds1a * $stake + $stake;
	if($eachway1){$total1 = ($odds1 / ($odds1a * $eachway1) * $stake) + $stake;}
	if($deadheat1){$total1 = $total1 / $deadheat1;}
	$total = $total1 * $odds2/$odds2a + $total1;
	if($eachway2){$total = ($odds2 / ($odds2a * $eachway2) * $total1) + $total1;}
	if($deadheat2){$total = $total / $deadheat2;}
	if(($status1 == "lose") || ($status2 == "lose")){$total = 0;}
	}

The variables odds1, odds1a etc are the odds entered in a web form
the variable stake is the entered stake from the form
rf1, status1, deadheat and eachway are all passed from the web form as well and are betting terminologies that i dont need to go into.

What i need is a function which i can call like this:

say we have a form with 2 bets:
If the odds for a bet are 2/1 then $odds1 = 2 and $odds1a = 1

function doublecalc ($odds1,$odds1a,$odds2,$odds2a,rf1,rf2,deadheat1,deadheat2,eachway1,eachway2,staus1,status2)

This function should return the value $total

Can someone help me with this please? if I can get 1 function working i can work out all the other bets types from there.

Thanks

[_SuperString]

The best way is to evaluate the bet type first and pass the available variables into a its function, for example:

Single bet:
$type = "single";
$var1 = "10";
$var2 = "2";

evaluation:

if(isset($_POST['type'])) {
    if($_POST['type'] == "single") {
     // pass details into single function
     $result = bet_single($var1, $var2);
   }
}

Function:

function bet_single($var1, $var2) {
  // do the calcualtions
  $end_value = ($var1*$var2) + $var2;
  return $end_value;
}

Output the results:

echo $results;

You should be able to build your functions using this method.

hope this helps