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Re: Is there a better way to group and sort objects?

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On Wed, 08 Aug 2018 06:57:33 -0400, Eric Sosman wrote:

> On 8/8/2018 4:20 AM, Martin Gregorie wrote:
>> On Tue, 07 Aug 2018 06:00:19 -0700, Eric Douglas wrote:
>> 
>>> I want to combine and sort objects by key properties and merge their
>>> secondary properties.  Is there a better way?  This is what I came up
>>> with..
>>>
>> Given your ..and sort... requirement, I'd use a TreeMap rather than a
>> HashMap because storing items in key sequence is implicit. In addition,
>> its search efficiency rises as the tree gets bigger; if the treemap
>> contains 2**23 entries a worst case search only does 23 key
>> comparisons.
> 
>      ... except that he sorts on a field of the mapped values,
> not on the map keys.  Specifically, if he has two instances with `var1'
> values of 2 and 10 they will sort in that order, but their map keys will
> sort in the order "10" followed by "2".

OK - missed that.



-- 
Martin    | martin at
Gregorie  | gregorie dot org

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Is there a better way to group and sort objects? Eric Douglas <e.d.programmer@gmail.com> - 2018-08-07 06:00 -0700
  Re: Is there a better way to group and sort objects? Eric Sosman <esosman@comcast-dot-net.invalid> - 2018-08-07 09:44 -0400
    Re: Is there a better way to group and sort objects? Eric Sosman <esosman@comcast-dot-net.invalid> - 2018-08-07 11:33 -0400
    Re: Is there a better way to group and sort objects? Eric Douglas <e.d.programmer@gmail.com> - 2018-08-07 10:22 -0700
      Re: Is there a better way to group and sort objects? Eric Sosman <esosman@comcast-dot-net.invalid> - 2018-08-07 14:16 -0400
        Re: Is there a better way to group and sort objects? Eric Sosman <esosman@comcast-dot-net.invalid> - 2018-08-07 14:36 -0400
        Re: Is there a better way to group and sort objects? Eric Douglas <e.d.programmer@gmail.com> - 2018-08-07 12:13 -0700
          Re: Is there a better way to group and sort objects? Eric Sosman <esosman@comcast-dot-net.invalid> - 2018-08-07 16:00 -0400
  Re: Is there a better way to group and sort objects? Martin Gregorie <martin@mydomain.invalid> - 2018-08-08 08:20 +0000
    Re: Is there a better way to group and sort objects? Eric Sosman <esosman@comcast-dot-net.invalid> - 2018-08-08 06:57 -0400
      Re: Is there a better way to group and sort objects? Martin Gregorie <martin@mydomain.invalid> - 2018-08-08 11:08 +0000
      Re: Is there a better way to group and sort objects? Martin Gregorie <martin@mydomain.invalid> - 2018-08-08 11:22 +0000
        Re: Is there a better way to group and sort objects? Eric Sosman <esosman@comcast-dot-net.invalid> - 2018-08-08 07:45 -0400
          Re: Is there a better way to group and sort objects? Martin Gregorie <martin@mydomain.invalid> - 2018-08-08 14:12 +0000
        Re: Is there a better way to group and sort objects? Eric Douglas <e.d.programmer@gmail.com> - 2018-08-08 05:50 -0700
          Re: Is there a better way to group and sort objects? Eric Sosman <esosman@comcast-dot-net.invalid> - 2018-08-08 09:23 -0400
            Re: Is there a better way to group and sort objects? Eric Douglas <e.d.programmer@gmail.com> - 2018-08-08 06:47 -0700
              Re: Is there a better way to group and sort objects? Eric Sosman <esosman@comcast-dot-net.invalid> - 2018-08-08 10:31 -0400
                Re: Is there a better way to group and sort objects? Eric Douglas <e.d.programmer@gmail.com> - 2018-08-08 08:24 -0700
          Re: Is there a better way to group and sort objects? Robert Klemme <shortcutter@googlemail.com> - 2018-08-14 14:06 +0200
            Re: Is there a better way to group and sort objects? Eric Douglas <e.d.programmer@gmail.com> - 2018-08-14 05:49 -0700
  Re: Is there a better way to group and sort objects? Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2018-08-09 16:06 +0200
    Re: Is there a better way to group and sort objects? Eric Douglas <e.d.programmer@gmail.com> - 2018-08-14 05:47 -0700

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