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I am trying to extract the lat long points for the polygons from a shapefile. I have followed the directions from the following links:

Getting list of coordinates for points in layer using QGIS?

How to extract geo data out of a polygon shapefile into CSV KWT

Example output:

OBJECTID    AREA    PERIMETER   AGENCY  NAME    REVDATE SQMILES Shape_Leng Shape_Area
1   0   0       Zone1   11/19/2014  0   237658.615  1531052792
2   0   0       Zone2   11/19/2014  0   739330.0369 7625960825
3   201487008   72063.20313 PF  Zone3   11/19/2014  231.6181139 985159.932 5260739790
4   0   0       Zone4   11/19/2014  0   1192796.221 15149531125
5   0   0       Zone5   11/19/2014  0   2040909.712 22577444695

So does this mean there are no lat/longs to extract?

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DonA
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  • http://gis.stackexchange.com/questions/24442/how-do-i-convert-a-polygon-into-a-point – Mapperz Dec 09 '14 at 19:09
  • I think your word 'point' should be vertices/node – Mapperz Dec 09 '14 at 19:09
  • I need the points that represent each polygon and there are 5 polygons. – DonA Dec 09 '14 at 19:16
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    convert to centroids vector>geomtery tools>polygon centroids will give you a point with attributes – Mapperz Dec 09 '14 at 19:22
  • Vector -> Geomtry Tools -> Extract Nodes -seems to pull out the parts I need. I now have to figure out the right lat/long conversion it seens to be in FEET or MILES - not decimal degrees. I picked WGS 84, but I may need to use the Project CRS - yes indeed! – DonA Dec 09 '14 at 19:35
  • Should I be using NAD 27 Northern Colorado vs WGS 84? I am in Northern Colorado? – DonA Dec 09 '14 at 19:37

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Vector -> Geometry Tools -> Extract Nodes will extract the lat/long points from all the polygons to a new shape file, then right click on this new layer and select SaveAs..., then build the csv file. Using the CRS layer from the project will automatically convert the points to the desired output - based on the projects CRS projection. Each were labeled with a polygon name, so separating them out was possible.

DonA
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