[postgis-devel] [PostGIS] #231: New distance-calculations proposal

[PostGIS]

#231: New distance-calculations proposal
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  Reporter:  nicklas      |       Owner:  robe         
      Type:  enhancement  |      Status:  assigned     
  Priority:  medium       |   Milestone:  postgis 1.5.0
 Component:  postgis      |     Version:               
Resolution:               |    Keywords:               
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Comment (by pramsey):

 Perhaps someone will post the canonical examples of
 representation/precision issues. Like the same mathematical answer giving
 different representations depending on what order the operands are
 applied. Anyhow, if I tell you that 0.99999999, 1.0 and 1.00000000000001
 all are the "same", does that give you a flavour? Different underlying
 ieee results that represent the same attempt at representing a double will
 spool out to different representations. Write up your own little test
 program that fires out 35 decimal places and try different little bits of
 math.  Unfortunately, our string writing code is kind of all hand-balled
 into place.  nice programmer rennovation might be to find all the places
 that print coordinates and build a standard API for them so we can control
 apparent output precision in one location.

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/231#comment:19>
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