[Date Prev][Date Next][Thread Prev][Thread Next]
[Date Index]
[Thread Index]
**Subject**: **Re: log/log10 in Lua 5.2.0-alpha**
**From**: Michal Kolodziejczyk <miko@...>
**Date**: Mon, 23 May 2011 11:34:22 +0200

On 20.05.2011 10:20, Dirk Laurie wrote:
>>
>> I don't understand the rational of the removal of math.log10 and the addition
>> of optional second parameter in math.log
> Maybe because there is no longer any strong reason why base 10 is
> any more special than base 2 or whatever.
I would say the API becomes cleaner.
>> It's a general implementation of log, but all opportunities of optimization
>> are lost.
>
> If you have an application that calculates logarithms base 10 so often
> that the unoptimized implementation slows it down unacceptably — then
> you write a very short module in C that supplies log10 directly.
...and then you (may) slow it down even further ;) Calling C module from
lua is quite expensive for such simple operations, so you really would
need to check if this way to go.
If the code remains pure-lua only, there will be greater chance for
luajit to optimize it.
Regards,
miko