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Re: Using HashBags

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From:
Fernando Santagata
Date:
April 7, 2018 11:02
Subject:
Re: Using HashBags
Message ID:
CAJ+jyGh-ZybJXdCiJtJfzBzqcMFgXiPKNUZoe_a-AVmoQ+7N5A@mail.gmail.com
Hi,

I'm not sure that I've understood what you need.
If you get that array of arrays from a another process @rows and you wish
to convert it into a Bag you can do this:

my @rows = [["JF", 1], ["JF", 2], ["MM", 2], ["MPu", 2], ["MM", 2], ["FE",
2], ["FV", 2], ["MPu", 2], ["JP", 2], ["JP", 2], ["FV", 2], ["FV", 2],
["JF", 2], ["MM", 2], ["MPu", 2], ["MM", 2], ["FE", 2], ["FV", 2], ["MPu",
2], ["JP", 2], ["JP", 2], ["JF", 4]];
my Bag $docents = bag @rows.map: -> @row {@row[0] xx @row[1]};
dd $docents;

# Bag $docents = ("JP"=>8,"FV"=>8,"FE"=>4,"MPu"=>8,"MM"=>8,"JF"=>9).Bag

Otherwise you can start collecting those pairs into a Bag from the start,
but we would need more details then.

HTH


On Sat, Apr 7, 2018 at 12:10 PM, mimosinnet <mimosinnet@gmail.com> wrote:

> Hi all,
>
> I do not seem to be able to get this done with the Bag or BagHash type:
>
> ---
> dd @rows;
>
> Output: Array @rows = [["JF", 1], ["JF", 2], ["MM", 2], ["MPu", 2], ["MM",
>> 2], ["FE", 2], ["FV", 2], ["MPu", 2], ["JP", 2], ["JP", 2], ["FV", 2],
>> ["FV", 2], ["JF", 2], ["MM", 2], ["MPu", 2], ["MM", 2], ["FE", 2], ["FV",
>> 2], ["MPu", 2], ["JP", 2], ["JP", 2], ["JF", 4]]
>>
>
> my %docents;
> for @rows -> @row {
>         %docents{ @row[0] } += @row[1];
> }
>
> dd %docents;
>
> Output: Hash %docents = {:FE(4), :FV(8), :JF(9), :JP(8), :MM(8), :MPu(8)}
>>
>
> ---
>
> As I understand it, this would better be achieved with the Bag or BagHash
> type. What would be the easy way?
>
> Thanks!
> --
> (≧∇≦) Mimosinnet (Linux User: #463211)
>



-- 
Fernando Santagata

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