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[woyler]

Hi all,
Can someone explain to me why MS returns the following values with these function calls?

convert.toint16(1.5) = 2 (this is expected)
convert.toint16(2.5) = 2 (huh?)
convert.toint16(3.5) = 4 (this is expected)
convert.toint16(4.5) = 4 (huh?)

the same is true for math.round. Can someone shed some light on this for me?
regards,
Bill

 

[ThatRickGuy]

Wow, stumped me. I even plugged it in here and got the same from both convert and ctype. I would have expected either a traditional rounding (.5 = 1, .4 = 0) or a truncate (.5 = 0), but not the inconsistent treatment.

-Rick

VB.Net Forum forum796 forum855 ASP.NET Forum
I believe in killer coding ninja monkeys.

 

[PRPhx]

Bill,
Take a look at the help for convert. I know it sounds very screwed up, but according to the help, your examples are working as they should. (here is a part of the explanation):

Return Value
value rounded to the nearest 16-bit signed integer. If value is halfway between two whole numbers, the even number is returned; that is, 4.5 is converted to 4, and 5.5 is converted to 6.

 

[woyler]

PRPhx,
Thanks for the info, and I noticed that pattern as well. My question still is why? I can not find a MS answer on this. There has to be some sort of explanation other then Joe Programmer @ MS ate too many "special brownies

 

[woyler]

Ahh. banker's rounding.
Because most of us work in the bank. I get it.

http://blogs.msdn.com/ericlippert/archive/2003/09/26/53107.aspx