Re: [boost] [xpressive] Performance Tuning?

Subject: Re: [boost] [xpressive] Performance Tuning?
From: Andrey Tcherepanov (moyt63c02_at_[hidden])
Date: 2009-07-29 22:10:46

On Wed, 29 Jul 2009 18:48:49 -0600, OvermindDL1 <overminddl1_at_[hidden]>  
wrote:

> Proceeding to timing tests.Calibrating overhead......done
> Timer overhead (t_c) ~= : 9.67512
> Jitter               ~= : 7.47951
> qi_parse vs atoi     : 78.1417 81.6005 86.3038% faster.
> qi_parse vs strtol  : 76.5284 85.2148 86.8329% faster.
> strtol vs atoi       : -4.67955 -2.60676 -0.488886% faster.
> qi_parse vs qi_parse : -0.900454 0.465715 1.85072% faster.

Folks, how do you get these 86% ?  What is the formula?
'cause I know I am missing something, since F(78.14,81.6) somehow gives  
0.86, but what is the F then...

Thank you very much,

   Andrey