Re: Why there are two diffrent result in two almost same formula

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What happens if you change

Single result2 = System.Convert.ToSingle(XNT * num) / SX;

to

Single result2 = System.Convert.ToSingle((XNT * num) / SX);


?

First one, you are modifying the left side before dividing. Second one, you
are modifying the result. I would suggest the second one would be correct.

--
Best regards,
Dave Colliver.
http://www.AshfieldFOCUS.com
~~
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"XjAcKs" <xjacks@xxxxxxxxx> wrote in message
news:eb4IoIb6JHA.5756@xxxxxxxxxxxxxxxxxxxxxxx
Thanks for you reply. My english is poor, so I will have to read your
reply for a while. If I find out something later, I will send a reply.

BTW: I just try the program in .NET 3.5/VS 2008, and the result the
same as .NET 2.0/VS 2005, so I think it seems not a complier bug or it
haven't been fixed.

I just try my code in Java language, and the expression's result is the
same value: 0.6985381. So I think the expression with ToSingle() method
is right...

I think I have figured out out.
I changed the variables definition "result" and "result2" to Double and I
delete the "SX" in expression. And it is :

int num = 3600;
Single XNT = 0.3F;
Double result = XNT * num ;
Double result2 = System.Convert.ToSingle(XNT * num);

And, the value of two result is:
result -> 1080.00004291534
result2 -> 1080

It seems that Single is more better than Double here...

Single result = (XNT * num) / SX;
Single result2 = System.Convert.ToSingle(XNT * num) / SX;

So I think in the first expression, the result of "XNT * num" is a type of
Double.

But why one Single variable multiply another Single variable, the result
is a type of Double? How weird it is...


.

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