get each pair from a string.

[wxjmfauth at gmail.com]

Le mardi 23 octobre 2012 06:59:49 UTC+2, rusi a écrit :
> On Oct 22, 9:19 pm, rusi <rustompm... at gmail.com> wrote:
> 
> > On 10/21/2012 11:33 AM, Vincent Davis wrote:
> 
> >
> 
> > > I am looking for a good way to get every pair from a string. For example,
> 
> > > input:
> 
> > > x = 'apple'
> 
> > > output
> 
> > > 'ap'
> 
> > > 'pp'
> 
> > > 'pl'
> 
> > > 'le'
> 
> >
> 
> > Maybe zip before izip for a noob?
> 
> >
> 
> > >>> s="apple"
> 
> > >>> [a+b for a,b in zip(s, s[1:])]
> 
> >
> 
> > ['ap', 'pp', 'pl', 'le']
> 
> 
> 
> Daniel wrote:
> 
> > This is a little bit faster:
> 
> >
> 
> > s = "apple"
> 
> > [s[i:i+2] for i in range(len(s)-1)]
> 
> 
> 
> Nice! I always find pairs of structural decomposition of input vs
> 
> recomposition of output interesting.
> 
> In this case the use of slices:
> 
> to decompose: s -> s[1:]
> 
> vs doing s[i:i+2]

Why bother with speeed?

The latest Python version is systematically slower
than the previous ones as soon as one uses non "ascii
strings".

Python users are discussing "code optimizations" without
realizing the tool they are using, has killed itself its
own performances.

(Replace 'apple' with 'ap需')

jmf