Re: [ANN] LuaCSV

[steve donovan <steve.j.donovan@...>]

On Mon, Aug 3, 2009 at 2:43 PM, Thomas Lauer<thomas.lauer@virgin.net> wrote:
> I have not yet looked into your code but one question springs to mind
> immediately: have you done some benchmarks (informal or otherwise), eg
> with a pure-Lua solution that works with LPEG or some other
> pattern-matching algorithms? I am confident that a low-level interface
> would be faster than pure Lua... the question is how much faster?

The results were rather interesting:

I compared against the pure Lua solution given in
http://lua-users.org/wiki/CsvUtils. My first result showed them
basically taking the same, until I realized that by default I'm doing
the floating-point conversion.

The target was a 20meg csv file, randomly generated rows of ten numbers.

(A) No floating-point conversion:
 lua: 1.94
 csv: 0.63

(B) Floating point conversion:
 lua: 4.22
 csv: 1.80

(This just added up all the numbers)

So the conversions are expensive; if you need them, it's cheaper to do
them in C.

steve d.