Calculate a string

[Intelly XAD]

Hi there, i've created a function that generates variate sums, for example: 5 * 4 / 20 - 5 =
This sum is saved under a string $sum="5 * 4 / 20 - 5 ="
But now I want the PHP code to calculate this sum for met is there any function available in PHP that can do this?
for example: calc($sum);

Many thnx in advance for the answers

[Barand]

try
[code]<?php
eval('$sum = 5 * 4 / 20 - 5 ;');
echo $sum;
?>[/code]

--> -4

[Intelly XAD]

Youre method works in the case you type it but when I type somthing like this it doesn't work:
<?php
$sum="5 + 20 / 5 - 4";
eval('$sum = $sum;');
?>

[wildteen88]

You are using single quotes. Variables dont work within single quotes. Use double quotes.

[sasa]

try[code]<?php
$sum="5 + 20 / 5 - 4";
eval("\$sum = $sum;");
echo $sum;
?>[/code]

[Intelly XAD]

Many thnx that worked...