Re: for/ if against dict - one liner

[Andrew Z]

Gentlemen,
 thank you very much for the replies and help.

Vincent's solution worked perfectly for me.
Alister - you are correct and for me, i was looking to achieve that -
readability and slightly less keystrokes.

On Tue, Nov 14, 2017 at 4:59 AM, alister via Python-list <
python-list@python.org> wrote:

> On Tue, 14 Nov 2017 00:44:18 -0500, Andrew Z wrote:
>
> > Hello,
> >  i wonder how do i get the "for" and "if" to work against a dictionary
> >  in
> > one line?
> >
> > basically i want to "squeeze":
> >  dct= [ 1 : "one", 2:"two", 3:"three"]
> >  for k, val in dct:
> >if k >= 2:
> >   # do magnificent things
> >
> > Thank you AZ
>
> why the need to single line it?
> is your computer running out of new line & space characters?
> it probably could be done with a dictionary comprehension but will that
> make things easier or harder to read/understand?
>
> "Readability counts"
>
>
>
>
> --
> (Presuming for the sake of argument that it's even *possible* to design
> better code in Perl than in C.  :-)
> -- Larry Wall on core code vs. module code design
> --
> https://mail.python.org/mailman/listinfo/python-list
>
-- 
https://mail.python.org/mailman/listinfo/python-list

Re: for/ if against dict - one liner

[Thomas Jollans]

On 2017-11-14 06:44, Andrew Z wrote:
> Hello,
>  i wonder how do i get the "for" and "if" to work against a dictionary in
> one line?
> 
> basically i want to "squeeze":
>  dct= [ 1 : "one", 2:"two", 3:"three"]
>  for k, val in dct:

Don't you mean dct.items()

>if k >= 2:
>   # do magnificent things
> 
> Thank you
> AZ
> 


-- 
Thomas Jollans
-- 
https://mail.python.org/mailman/listinfo/python-list

Re: for/ if against dict - one liner

[alister via Python-list]

On Tue, 14 Nov 2017 00:44:18 -0500, Andrew Z wrote:

> Hello,
>  i wonder how do i get the "for" and "if" to work against a dictionary
>  in
> one line?
> 
> basically i want to "squeeze":
>  dct= [ 1 : "one", 2:"two", 3:"three"]
>  for k, val in dct:
>if k >= 2:
>   # do magnificent things
> 
> Thank you AZ

why the need to single line it?
is your computer running out of new line & space characters?
it probably could be done with a dictionary comprehension but will that 
make things easier or harder to read/understand?

"Readability counts"




-- 
(Presuming for the sake of argument that it's even *possible* to design
better code in Perl than in C.  :-)
-- Larry Wall on core code vs. module code design
-- 
https://mail.python.org/mailman/listinfo/python-list

Re: for/ if against dict - one liner

[Vincent Vande Vyvre]

Le 14/11/17 à 06:44, Andrew Z a écrit :

Hello,
  i wonder how do i get the "for" and "if" to work against a dictionary in
one line?

basically i want to "squeeze":
  dct= [ 1 : "one", 2:"two", 3:"three"]
  for k, val in dct:
if k >= 2:
   # do magnificent things

Thank you
AZ


Maybe something like that:

lst = [do_magnificent_thing(dct[k]) for k in dct if k >= 2]

lst contains the returns of do_magnificent_thing(k) in unpredictable order.


Vincent

--
https://mail.python.org/mailman/listinfo/python-list

Re: for/ if against dict - one liner

[Thomas Jollans]

On 2017-11-14 07:29, Stefan Ram wrote:
> Andrew Z  writes:
>> i wonder how do i get the "for" and "if" to work against a dictionary in
>> one line?
> 
> dict ={ 1 : "one", 2 : "two", 3 : "three" }
> print( *( ( str( key )+ ' ' + str( dict[ key ])) for key in dict if key >= 2 
> ), sep='\n' )
> 
>   prints:
> 
> 2 two
> 3 three
> 

We can build something nicer than that, surely. The repeated str() calls
and dictionary lookups just look like noise to my eyes.

print('\n'.join(f'{k} {v}' for k, v in dict.items() if k >= 2))

But indeed, you can build concise dictionary filters like that with
generator expressions and list comprehensions.


-- 
Thomas Jollans
-- 
https://mail.python.org/mailman/listinfo/python-list

for/ if against dict - one liner

[Andrew Z]

Hello,
 i wonder how do i get the "for" and "if" to work against a dictionary in
one line?

basically i want to "squeeze":
 dct= [ 1 : "one", 2:"two", 3:"three"]
 for k, val in dct:
   if k >= 2:
  # do magnificent things

Thank you
AZ
-- 
https://mail.python.org/mailman/listinfo/python-list