[QGIS-trac] [Quantum GIS] #3500: FTOOLS Calculate Area error

[Quantum GIS]

#3500: FTOOLS Calculate Area error
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   Reporter:  enrico80                          |              Owner:  borysiasty   
       Type:  bug                               |             Status:  new          
   Priority:  major: does not work as expected  |          Milestone:  Version 1.7.0
  Component:  Python plugins and bindings       |            Version:               
   Keywords:  ftools                            |   Platform_version:               
   Platform:  Debian                            |           Must_fix:  No           
Status_info:  0                                 |  
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 Hi,
 I try to calculate area with ftools add geometry column. I have noted that
 in automatic new field “AREA” have this properties type=real lenght=10 >
 precision=6, this involve an error, some numbers are lost, because the
 Area number have lenght>10.
 Example: if I calculate Piedmont area with Ftools obtain 2539107283
 if I calculate the same Area , add new column (type real lenght=20
 precision=5) and use calc field ($area) I obtain 25391072834.9971.

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Ticket URL: <https://trac.osgeo.org/qgis/ticket/3500>
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