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Subject: Re: [Boost-users] [numeric::convert] RoundNearest?
From: Diederick C. Niehorster (dcnieho_at_[hidden])
Date: 2011-07-03 06:28:25

Dear All,

And for a related question:
Why is promote used in the example at

Is it somehow advantageous to convert a double to an int if the input
type is float, or likewise to do int to double conversion when the
input type is char?

I hope someone could shed light on the benefits of this.

Thank you!

On Sun, Jul 3, 2011 at 18:21, Diederick C. Niehorster <dcnieho_at_[hidden]> wrote:
> Dear All,
> I have just discovered Boost.NumericConvert, useful and a nice effort!
> However, I am missing a RoundNearest function for float to int
> conversions, with only RoundEven being provided.
> RoundEven of course does exactly what it is described to do, rounding
> .5 to 0 and 1.5 to 2, but i'd like the highschool (usual?) behavior of
> rounding up when a number exactly in the middle is provided. I can
> implement it myself by slightly modifying RoundEven of course, but I
> am wondering if I am missing something obvious or whether there is a
> good reason why this function is not included?
> Thank you very much for any thoughts!
> Best,
> Dee

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