keywords in LightRoom

Doug Brewer doug at
Wed Oct 7 12:12:34 EDT 2009

Graydon wrote:
> On Tue, Oct 06, 2009 at 06:39:18PM -0400, Doug Franklin scripsit:
>> Graydon wrote:
>>> Yeah, but I got taught data structures by a graph theorist, and we did
>>> graphs, acyclic graphs, directed graphs, and then acyclic directed
>>> graphs, so my brain thinks the acyclic is a special case of directed,
>>> rather than the other way around.
>> That taxonomy is not acyclic. :-)
> Behold the weakness of adjectives! :)
>> [Directed and acyclic are orthogonal characteristics when applied to  
>> graphs.  A graph may be either, neither, or both.]
> Sure.  And strictly, strictly, "directed" and "acyclic" both modify
> "graph", rather than each other, so the phrases are completely
> equivalent, only you'd have to be a grammar robot to read it that way,
> which is why a native speaker doesn't think "directed acyclic graph" and
> "acyclic directed graph" sound like necessarily the same thing.
> Which is how I got into this particular excavation in the first place,
> and I should stop digging. :)
> -- Graydon

am I the only one who kept having my brain read this exchange as about 
acrylic graphs and longing for the good old days of oil-based?

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