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- Subject: Re: [ANN] Lua 5.3.0 (work1) now available
- From: Roberto Ierusalimschy <roberto@...>
- Date: Sat, 6 Jul 2013 16:36:03 -0300
> So, for best efficiency, I guess programmers will have to be careful
> to avoid unnecessary int -> fp conversions
> Suppose I read a large number of values (some integer, some not)
> from a text file into a table and then perform extensive
> computations on them.
> Should I multiply each value by 1.0 (or add 0.0), to pre-convert all
> of them to fp, to avoid slowing down the following computations
> compared to Lua 5.2?
There are two formats for reading numbers: io.read("*n") always reads
a floating-point number, and io.read("*i") always reads an integer.
So, usually there is no need to convert anything.
> A doubt: does math.floor return an fp value or an integer?
> (the manual could be interpreted as the latter)
Just after the section "Mathematical Functions", the manual says this:
"Unless stated otherwise, all functions in this library operate with and
return floating-point numbers."
There is a new function, math.ifloor, that returns the floor as an integer.
> Lastly, I see no bit64 ops in the manual; will they come?