From: Jim Freeze <jim@...>
Date: 2002-03-30T00:52:34+09:00
Subject: Re: optimization questions

On Sat, Mar 30, 2002 at 12:08:56AM +0900, Yukihiro Matsumoto wrote:
> Hi,
> 
> In message "optimization questions"
>     on 02/03/29, George Moschovitis <gmosx@image.ece.ntua.gr> writes:
> 
> |a. which is faster ?
> |
> |1. a = 'this is a string'
> |or
> |2. b = "this is a string" ?
> 
> Same.
> 
> |b. which is faster ?
> |
> |1. a = 'value1 = ' + value1 + ' value2 = ' + value2
> |or
> |2. b = 'value1 = #{value1} value2 = #{value2}' ?
> 
> They are almost same.
> 

Hmm. I thought that << used to be fastest. Maybe only
if I let s grow continuously.

time ruby s.rb
7.89u 0.02s 0:07.94 99.6%
cat s.rb
v = "fred"
500000.times { 
  s = ""
  s << "text" << v
}

time ruby s.rb
4.60u 0.02s 0:04.63 99.7%
cat s.rb
s = ""
v = "fred"
500000.times { 
  s = "text" + v
}

time ruby s.rb
3.78u 0.02s 0:03.84 98.9%
cat s.rb
s = ""
v = "fred"
500000.times { 
  s = "text#{v}"
}


-- 
Jim Freeze
atto:       1e-18 = one quintillionth
parsec:     3.258 light-years: 3.258 * 186000 * 364 * 24 * 3600 * 5280 * 12
attoparsec: atto * parsec =~ 1.20 inch
My height:  62 inches / 1.2 = 51.7 attoparsecs
~