Re: Rounding off a double precision variable

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Article #4136

#4136

From: Kaspar Daugaard
Date: Fri, 24 Mar 2000 00:00

23 lines
1925 bytes

Paul Meyerholtz wrote:
> A question about the function floor() from a newbie.  If I'm trying to
> round off doubles the following seems to work:
> 
> double x;
> ....   x assigned some number ....
> int rounded = int(x +.5);
> 
> Is this compiler dependent?  Don't C++ programs truncate when converting
> from double to int?


You should note that using floor() is different from truncating when the
value is negative, e.g. floor(-2.4) is -3 while int(-2.4) is -2.

- Kaspar

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Subject: Re: Rounding off a double precision variable
Date: 2000/03/24
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