get method

Aaron Brady castironpi at gmail.com
Tue Dec 30 03:35:21 CET 2008


On Dec 29, 8:02 pm, Steven D'Aprano <st... at REMOVE-THIS-
cybersource.com.au> wrote:
> On Mon, 29 Dec 2008 17:38:36 -0800, Ross wrote:
> > On Dec 29, 8:07 pm, Scott David Daniels <Scott.Dani... at Acm.Org> wrote:
> >> Ross wrote:
> >> > ... Use get to write histogram more concisely. You should be able to
> >> > eliminate the if statement.
>
> >> > def histogram(s):
> >> >    d = dict()
> >> >    for c in s:
> >> >            d[c]= d.get(c,0)
> >> >    return d
>
> >> > This code returns a dictionary of all the letters to any string s I
> >> > give it but each corresponding value is incorrectly the default of 0.
> >> > What am I doing wrong?
>
> >> How is this code supposed to count?
>
> >> --Scott David Daniels
> >> Scott.Dani... at Acm.Org
>
> > I realize the code isn't counting, but how am I to do this without using
> > an if statement as the problem instructs?
snip
> So what you need is:
>
> * set d[c] to whatever d[c] already is plus one, or 0 plus one if it
> isn't already there.
>
> It's a two character change to one line. Let us know if you still can't
> see it.

That's actually really sophisticated.  Steven is being really clever
here, by writing a number in an unusual way.

He said:

* set d[c] to whatever d[c] already is plus one, or 0 plus one if it
isn't already there.

It is the same as:

* set d[c] to whatever d[c] already is plus one, or one if it
isn't already there.

Side-by-side.  Perhaps you will learn his secret someday.  It has to
do with 0+1=1.

Armed with it, he has:

something something +1, something something something +1

Which brings us (to):

( something something, something something something ) +1

Three cheers for thinking.



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