[QGIS-trac] [Quantum GIS] #3330: Bug: Glitches in Pretty Breaks graduated rendering

[Quantum GIS]

#3330: Bug: Glitches in Pretty Breaks graduated rendering
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   Reporter:  Alister                           |              Owner:  nobody       
       Type:  bug                               |             Status:  new          
   Priority:  major: does not work as expected  |          Milestone:  Version 1.7.0
  Component:  Symbology                         |            Version:  Trunk        
   Keywords:                                    |   Platform_version:  XP           
   Platform:  Windows                           |           Must_fix:  No           
Status_info:  0                                 |  
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 Sometimes using "Pretty Breaks" mode the graduated renderer creates
 unnecessary categories which are larger than the maximum value in the
 data.  The biggest category still has the maximum value as its upper
 limit.

 e.g. in the screenshot attached where the ZN column is used, the maximum
 value in the data is 1.58

 in the screenshot where the CU column is used, the maximum value in the
 data is 0.145

 Because so many extra columns are created in the CU example the effect on
 the map is much worse, as all the data ends up in a narrow slice of the
 colour ramp (all the data is be yellow).

 I've joined most of the attribute data to some made up shapes and attached
 it for an example (a few of the shapes got deleted when using the "join
 attributes" tool for some reason, but it still has the same problems when
 using "Pretty Breaks").

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Ticket URL: <https://trac.osgeo.org/qgis/ticket/3330>
Quantum GIS <http://qgis.org>
Quantum GIS is an Open Source GIS viewer/editor supporting OGR, PostGIS, and GRASS formats