getting the numerator / denominator of a fraction

[SpartaRotterdam]

IE:

$x = 0.125

But I want to know what fraction $x is the result of!
In this case: the numerator should be: 1 and the denominator should be 8

another example:
$x = 0.333333333333

the numerator should be 1
the denominator should be 3

This is approximately off couse and that's the trick!

Any ideas?!

I have a JavaScript which works but when I code it in PHP it won't! Please help!

this is the JavaScript:

<script language="JavaScript">
<!--
function RatFrac(x, tol) 
{
    var tol0 = 1e-10;
    var maxIt = 50;  

var xi=x;
var d=[];
var n,ni,t;
var i,j;

if (typeof(tol)=='undefined')
{
    tol = tol0;
}

for (i=0; i<maxIt; i++)
{
    d[i] = Math.round(xi);
    xi = 1/(xi-d[i]);

    t = d[i];
    n = 1;
    for (j=i-1; j>=0; j--)
    {   
        ni = n;
        n = t;
        t = ni+t*d[j];
    }
    if (n<0) 
    {
        n = -n;
        t = -t;
    }

    if ((Math.abs(t/n-x)<tol)) 
    {
        break;
    }
}
return [n,t];
}        

x = 0.0947;
f = RatFrac(x,1e-10);
n = f[0];
t = f[1];

alert("numerator: " + t + "\n\rdenominator: " + n);
//-->
</script>