Re: [boost] [graph] dijkstra pull request ping

Subject: Re: [boost] [graph] dijkstra pull request ping
From: Piotr Wygocki (vwygos_at_[hidden])
Date: 2015-10-21 09:22:53

Dear Alex,

Thank you for your feedback!

  I can see that is useful, but it is not
> Dijkstra's algorithm.
>

Could you give the reference to the "real" Dijkstra algorithm? We are
talking about implementation detail which was
not concerned at all in the original Dijkstra paper. Note, that standard
dijkstra call with default distance map works
exactly the same with or without my patch. IMHO, the current conception
(without my patch) is caused only by using BFS abstraction.
Try to modify my code to achieve previous functionality and you find it
really awkward.

> This does not seem a real problem. The BFS function is well suited to
> Dijkstra's algorithm, perhaps the only problem is that its name is not
fully
> appropriate.

It is important to make proper abstractions. As I previously said BFS could
be expressed as Dijkstra with custom  priority queue
implemented as FIFO. It does not work the other way around. Dijkstra is NOT
a special kind of BFS. Implementation happens to be similar, which was used
in this case (which is bad IMO).

Regards,

Piotr