The power operator in Java?

Question

When I run the following Visual Basic code :

Dim b As Double
b = (2 ^ 16 - 1) * Math.Sqrt(Math.Sqrt((a / (2 ^ 8 - 1))))

(Assuming a is a double whose value is 15.0)
The result I get for b is about 32,275.

But when I run the following Java code, which is supposed to do the same as above:

double b;
b = (2 ^ 16 - 1) * Math.sqrt(Math.sqrt((a / (2 ^ 8 - 1))));

Again with a being 15, I get a much different result: about 17.

Both are solving this equation:

enter image description here

Why is this so? For what I'm working on, the Visual Basic yields result I'm looking for.

score 32 · Accepted Answer · answered Aug 18 '11 at 01:49

32

^ is XOR operator in java. Use Math.pow(2,8) which is 2 ^ 8 in Visual Basic.

answered Aug 18 '11 at 01:49

Eng.Fouad

1

Besides the XOR thing, in Java a is int or double? Because if its int, then a / x is int too. – pablosaraiva Aug 18 '11 at 01:51
`a` is a double value in this case. – Kenan Aug 18 '11 at 01:54
Thanks! This solution worked. I was wondering why `Math.pow()` even existed if I could just use `^` (which I now know I can't). – Kenan Aug 18 '11 at 02:00
2

Nice succinct answer (1+), Eng. Congratulations on the high number of up-votes! – Hovercraft Full Of Eels Aug 18 '11 at 02:42

1 Answers1