Opera JavaScript Flaw--Computation Error
Our web spider found the following code snippet at home_hiwaay_net and contains information about acos and JavaScript.
acos (Math.sin (y1) * Math.sin (y2) 
+ Math.cos (y1) * Math.cos (y2) * Math.cos (x1-x2))); 

document.write ("<P><STRONG>First computation:</STRONG> dist =
 " + dist); 
// Second computation (does not evaluate correctly) 
dist = (Math.acos (Math.sin (y1) * Math.sin (y2) 
+ Math.cos (y1) * Math.cos (y2) * Math.cos (x1-x2))) * R; 

document.write ("<P><STRONG>Second computation:</STRONG> dist 
= " + dist); 
//     --> 
</SCRIPT> 
Results 
The results of the script appear below (provided you have JavaScript 
enabled).  The numbers should be the same, but in Opera 3.0, they are 
different (the second result is incorrect). 
Discovered By 
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