Re: Question about rtrees (overleft replacing left in nodes)

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От
William White
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Re: Question about rtrees (overleft replacing left in nodes)
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406B364F.2040000@frognet.net
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Question about rtrees (overleft replacing left in nodes) "bwhite" <bwhite@frognet.net>
Re: Question about rtrees (overleft replacing left in nodes) Tom Lane <tgl@sss.pgh.pa.us>
Re: Question about rtrees (overleft replacing left in nodes) William White <bwhite@frognet.net>
Re: Question about rtrees (overleft replacing left in nodes) Tom Lane <tgl@sss.pgh.pa.us>
Re: Question about rtrees (overleft replacing left in nodes) William White <bwhite@frognet.net>
Re: Question about rtrees (overleft replacing left in nodes) Tom Lane <tgl@sss.pgh.pa.us>
Re: Question about rtrees (overleft replacing left in nodes) William White <bwhite@frognet.net>
Re: Question about rtrees (overleft replacing left in nodes) Tom Lane <tgl@sss.pgh.pa.us>
Re: Question about rtrees (overleft replacing left in nodes) Tom Lane <tgl@sss.pgh.pa.us>
Re: Question about rtrees (overleft replacing left in nodes) William White <bwhite@frognet.net>
Re: Question about rtrees (overleft replacing left in nodes) Tom Lane <tgl@sss.pgh.pa.us>
Tom Lane wrote:

> Right, but what about the existing operators --- what is a more correct
> way to document them?

Ouch.

Appealing to J.F. Allen's terminology ("An Interval-Based Representation 
of Temporal Knowledge", Comm ACM 26(11) 832-43), overleft could be 
called "left or finishes" (implying all other related conditions, of 
which there are a bunch) but this relies too heavily on time notation I 
think.  "right boundary left of right boundary" is accurate but rather 
verbose, "rightoverleft" too confusing.  Of course, I suspect most 
people will see the operator, not the C function name; if they see the 
latter they can read the code anyway.

Perhaps document as S &< T iff S "does not extend to the right 
of/beyond" (the right boundary of) T?  And either leave the C functions 
as-is or give them reasonable names; in either case, "a.high.x <= 
b.high.x" is just as clear as any comment.

-- Bill
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