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From: Grant Edwards <invalid@invalid.invalid>
Newsgroups: comp.os.linux.development.apps
Subject: Re: cast double to short problem
Date: Wed, 7 Mar 2012 00:30:52 +0000 (UTC)
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On 2012-03-06, Bill M <wpmccormick@just_about_everywhere.com> wrote:

>> What exactly are you trying to accomplish with the above code?
>
> I need to interface to another system that does not accept floating 
> point values. It's interface specifies that certain values are X 10. 
> other are X 100.

> Sounds like maybe what I need is a intermediate round operation?

What you were doing was truncating (2.999999999999999 -> 2), and I
suspect you want is indeed rounding to the nearest integer FP value
followed by the conversion to integer:

 2.999999999999999 -> 3.0000000000000 -> 3

 
$ man round

#include <math.h>

i = (short) round(MyDoubleValue * 100.0);