[QGIS-trac] Re: [Quantum GIS] #2658: QgsVectorLayer.select( QgsVectorLayer.extent(), true) does not return all features

[Quantum GIS]

#2658: QgsVectorLayer.select( QgsVectorLayer.extent(), true) does not return all
features
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        Reporter:  ersts                             |         Owner:  nobody       
            Type:  bug                               |        Status:  closed       
        Priority:  major: does not work as expected  |     Milestone:  Version 1.5.0
       Component:  Vectors                           |       Version:  HEAD         
      Resolution:  wontfix                           |      Keywords:               
Platform_version:  Ubuntu 10.04                      |      Platform:  Linux        
        Must_fix:  Yes                               |   Status_info:  0            
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Changes (by wonder):

  * status:  new => closed
  * resolution:  => wontfix

Comment:

 Peter,

 you should use empty extent {{{QgsRectangle()}}} to tell the layer that
 you need all features. That is not only safer, but can be also faster as
 there is no spatial filtering going on.

 I believe the problem is caused by some subtle differences among the
 values of floating point numbers of coordinates. For example, extent
 passed to PostGIS database is first encoded as a string and then decoded
 back to double value, so there is obvious space for loosing the precision.

 Martin

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Ticket URL: <https://trac.osgeo.org/qgis/ticket/2658#comment:1>
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