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Re: Convert list to another form but providing same information

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Maurice <mauricioliveiraguarda@gmail.com> writes:

> Hello, hope everything is okay. I think someone might have dealt with
> a similar issue I'm having.
>
> Basically I wanna do the following:
>
> I have a list such [6,19,19,21,21,21] (FYI this is the item of a
>certain key in the dictionary)
>
> And I need to convert it to a list of 32 elements (meaning days of the
> month however first element ie index 0 or day zero has no meaning -
> keeping like that for simplicity's sake).

> Therefore the resulting list should be:
> [0,0,0,0,0,0,1,0,0,0...,2,0,3,0...0]

How about

  reduce(lambda counts, day: counts[:day] + [counts[day]+1] + counts[day+1:],
         days, [0]*32)

?  (reduce is in functools).

Not efficient, but sometimes you just want to the job done.

More efficient would be:

  def inc_day(counts, day): counts[day] += 1; return counts
  reduce(inc_day, days, [0]*32)

For experts here: why can't I write a lambda that has a statement in it
(actually I wanted two: lambda l, i: l[i] += 1; return l)?

<snip>
-- 
Ben.

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Convert list to another form but providing same information Maurice <mauricioliveiraguarda@gmail.com> - 2016-03-21 11:26 -0700
  Re: Convert list to another form but providing same information Maurice <mauricioliveiraguarda@gmail.com> - 2016-03-21 11:30 -0700
    Re: Convert list to another form but providing same information Mark Lawrence <breamoreboy@yahoo.co.uk> - 2016-03-21 19:24 +0000
    Re: Convert list to another form but providing same information anantguptadbl@gmail.com - 2016-03-22 07:23 -0700
  Re: Convert list to another form but providing same information Mark Lawrence <breamoreboy@yahoo.co.uk> - 2016-03-21 19:21 +0000
  Re: Convert list to another form but providing same information Peter Otten <__peter__@web.de> - 2016-03-21 20:22 +0100
  Re: Convert list to another form but providing same information Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-03-21 20:03 +0000
    Re: Convert list to another form but providing same information Ian Kelly <ian.g.kelly@gmail.com> - 2016-03-21 14:12 -0600
      Re: Convert list to another form but providing same information Ben Bacarisse <ben.usenet@bsb.me.uk> - 2016-03-22 00:31 +0000
        Re: Convert list to another form but providing same information Chris Angelico <rosuav@gmail.com> - 2016-03-22 11:58 +1100
        Re: Convert list to another form but providing same information Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2016-03-22 15:34 +1100
    Re: Convert list to another form but providing same information Ian Kelly <ian.g.kelly@gmail.com> - 2016-03-21 14:14 -0600
  Re: Convert list to another form but providing same information Steven D'Aprano <steve@pearwood.info> - 2016-03-22 11:13 +1100
  Re: Convert list to another form but providing same information Paul Rubin <no.email@nospam.invalid> - 2016-03-21 18:35 -0700
    Re: Convert list to another form but providing same information Steven D'Aprano <steve@pearwood.info> - 2016-03-22 21:49 +1100

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