Python and STL efficiency

[Ray]

Neil Cerutti wrote:
> I don't see why it should run a lot faster that way.
>
> Appending elements to a vector with push_back takes amortized
> constant time. In the example above, preallocating 40000 strings
> saves (probably) math.log(40000, 2) reallocations of the vector's
> storage along with the consequent copy-construction and
> destruction of some fixed number of strings. Most of those
> reallocations take place while the vector is still proportionally
> quite small.

I see your logic, however it does make it run a lot faster. On my
machine, with 1000000 repetition, what used to take 5+ seconds now
takes only about 1+++ to 2 secs. 

> 
> -- 
> Neil Cerutti