using "*" to make a list of lists with repeated (and independent) elements
88888 Dihedral
dihedral88888 at googlemail.com
Sat Sep 29 13:01:30 EDT 2012
On Saturday, September 29, 2012 9:46:22 PM UTC+8, Ramchandra Apte wrote:
> On Thursday, 27 September 2012 04:14:42 UTC+5:30, Tim Chase wrote:
>
> > On 09/26/12 17:28, 88888 Dihedral wrote:
>
> >
>
> > > 88888 Dihedral於 2012年9月27日星期四UTC+8上午6時07分35秒寫道:
>
> >
>
> > >>>> In these conditions, how to make this list [[0,0,0],[0,0,0]] with "*"
>
> >
>
> > >>>> without this behavior?
>
> >
>
> > >>> >>> a = [[0]*3 for i in xrange(2)]
>
> >
>
> > >>> >>> a[0][0]=2
>
> >
>
> > >>> >>> a
>
> >
>
> > >>> [[2, 0, 0], [0, 0, 0]]
>
> >
>
> > >
>
> >
>
> > > def zeros(m,n):
>
> >
>
> > > a=[]
>
> >
>
> > > for i in xrange(m):
>
> >
>
> > > a.append([0]*n)
>
> >
>
> > > return a
>
> >
>
> > >
>
> >
>
> > > If one wants to tranlate to C, this is the style.
>
> >
>
> >
>
> >
>
> > But this is Python, so why the heck would anybody want to emulate
>
> >
>
> > *C* style? It could also be written in an assembly-language style,
>
> >
>
> > COBOL style, or a Fortran style...none of which are particularly
>
> >
>
> > valuable.
>
> >
>
> >
>
> >
>
> > Besides, a C-style would allocate a single array of M*N slots and
>
> >
>
> > then calculate 2d offsets into that single array. :-P
>
> >
>
> >
>
> >
>
> > -tkc
>
>
>
> 88888 Dihedral is a bot.
Don't you get it why I avoided the lambda one liner as a functon.
I prefer the def way with a name chosen.
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