Python and STL efficiency

[Tim N. van der Leeuw]

Maric Michaud wrote:
> Le mardi 22 août 2006 12:55, Mc Osten a écrit :
> > In fact Python here is faster. Suppose it has a really optimized set
> > class...
>
> Maybe I'm missing something but the posted c++codes are not equivalent IMO to
> what python is doing. I discarded the "slow" version, and tried to get the
> equivalent in c++ of :
>

Your C++ version got me the following timings (using gcc 3.4.5 as the
compiler, MinGW version, with -O6):

LeeuwT at nlshl-leeuwt ~/My Documents/Python
$ ./testcpp.exe
print_occurence_of_strings
What do you know?
chicken crosses road
fool
so long...
print_occurence_of_unique_strings
What do you know?
chicken crosses road
fool
so long...
print_occurence_of_unique_strings_compared_by_address
What do you know?
chicken crosses road
fool
so long...
strings : 2.135
unique strings : 1.103
compared by address : 0.21


For reference, Python's best time was 0.39 seconds on the same computer
(in the 'fast' version, using only 4 unique string instances).

Hmmm... Can we conclude now that carefully crafted C++ code is about
twice as fast as casually and intuitively written Python code? ;) (Just
kidding here of course)

NB: Your code now tests for address-equality. Does it also still test
for string-equality? It looks to me that it does, but it's not quite
clear to me.

Cheers,

--Tim