[GNC-dev] Transaction matcher, code to detect many-to-one matches?

[jean laroche]

I fully agree that it's non trivial. It's a combinatorial problem in 
theory, to find the match that gives the highest overall score.
But this is academic musing! In practice, we're not faced with 
complicated types of scenario and the matcher only has to give a "good" 
solution, not necessarily the best.

But in any case, it should definitely NOT offer to match all OFX to the 
same account transaction!
That's just a bug.
Also, it should not try to match an OFX transaction to an already 
cleared, or reconciled transaction.
That's also a bug.

Jean


On 5/7/2020 2:20 AM, Christopher Lam wrote:
> It's very non-trivial. Consider simplified examples:
>
> OFX
> 02/01/20 DESC $25
> 04/01/20 DESC $25
> 06/01/20 DESC $25
>
> Account
> 01/01/20 DESC $25
> 03/01/20 DESC $25
> 03/01/20 DESC $25
> 05/01/20 DESC $29
>
> They all could match each other. There's always a score that exists 
> between any OFX-split and Account-split. eg the first splits will have 
> a high score, and the last lines will have a low score due to the 
> amount discrepancy. The automatcher should prepare a match list that 
> maximises the "good" matches e.g. 02/01/20(OFX) to 01/01/20(account), 
> and does not attempt matches below an arbitrary threshold e.g. 
> 04/01/20(OFX) to 05/01/20(account).
>
> The answer will lie somewhere in 
> https://en.wikipedia.org/wiki/Matching_(graph_theory) 
> <https://en.wikipedia.org/wiki/Matching_%28graph_theory%29>
>
> C
>
> On Thu, 7 May 2020, 12:46 pm jeanl, <ripngo at gmail.com 
> <mailto:ripngo at gmail.com>> wrote:
>
>     What about this question?
>
>     On a related note, is it expected that an already-cleared transactions
>     should appear in the list of matches, if the "Enable update match
>     action"
>     option isn't on? It seems that it shouldn't but maybe I don't quite
>     understand the match logic...
>
>     Jean
>
>
>
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