Re: math.floor and rounding

[Tony Finch <dot@...>]

On Mon, 20 Sep 2010, Jose wrote:
>
> I want to round numbers with two decimal digits. I use math.floor( n *
> 100 )  but sometimes I have situations like:
> 	n = 10.20; math.floor( n * 100 ) --> 1019
> My current solution is to always add 0.001 to n, but is this the right
> approach ?

You should add 0.005 to get (roughly) round-to-nearest.

Lua is a little bit weak in this area because C89 doesn't have a
round-to-nearest function (only floor and ceil). (C99 is more complete.)

Tony.
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