#137: ST_ShortestLine, ST_LongestLine, ST_max_distance, ST_DFullyWithin
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Reporter: post... at jordogskog.no | Owner: robe
Type: enhancement | Status: assigned
Priority: medium | Milestone: postgis 1.5.0
Component: postgis | Version:
Resolution: | Keywords:
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Comment (by robe):
Nicklas,
Sorry I haven't been very encouraging looking at the patches. I promise
once things settle down and we hmm finally release 1.4.0 (HINT HINT).
I'll pay more attention to your patch.
I do have one for you to try out. I took united states (fairly high
resolution version) and unioned each together to get an individual record
for each state. To demonstrate the cascade union power of 1.4, but now
ST_Distance is hmm - incredibly slow.
So here is one for you to chump on:
SELECT a.state As st_a, b.state As st_b, ST_Distance(a.the_geom,
b.the_geom) As dist_m
FROM states AS a
CROSS JOIN states AS b
WHERE a.state = 'Maine' and b.state = 'Rhode Island';
The above query takes 4.7 seconds on our current 1.3 and 1.4 distance
implementations and returns
131103.250239575
If I do distance between Texas and California -- lets just say its so
painful, I don't even have the patience to wait for it to complete.
So I would be interested in seeing what timings you get with these and the
answers with your revised routines.
I'll attach the data set shortly.
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Ticket URL: <http://trac.osgeo.org/postgis/ticket/137#comment:16>
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