I have run k-LoCoH on OpenJump and am attempting to calculate the area of the home range. It is on a shapefile layer of the reserve the animal's GPS points are in (CSV). I have followed the manual to generate the Attributes and added Area and Perimeter to the table as explained. It generates a set of numbers for each polygon but I have no idea how this relates to area?

For example, one of the Attribute lines under the Area column has the number 8.127215840943213E-8. The largest polygon (the one I actually want the area of as it is the entire area) has the smallest number (0.013416734281735664). How can I convert this to a meaningful area estimate? Do I need to add the areas together? And how does this link to the shapefile of the reserve borders it is displayed with as they are not linked? Does this automatically calculate area as it is geo-referenced?

Apologies for all the questions but this has been driving me crazy for the last two weeks...


Home Range Calculation Manual suggests this plugin assumes data points you have given are in UTM coordinates. As your GPS are likely in latitude and longitude, output unit is in degrees^2.

If you are working in equatorial area, your 0.013416734281735664 would mean 165 km2 and 8.127215840943213E-8 would be 0.001 km2. It depends where you are.

There may be online conversion website, but reprojecting your GPS data to appropriate UTM beforehand would be more practical. (OpenJUMP seems to have a Coordinate Transform Plugin, but I have no idea how to work on it).

EDIT -- Update following the comment by user30184

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Coordinate Transformation plugin, which is also available in PLUS version, can be used to reproject your geographical (latlon) coordinates to UTM.

After turning your point layer into Editable mode, the plugin become available to activate. Please select Registry: EPSG, Source: 4326 and appropriate UTM zone as the Target.

To find out relevant EPSG code, EPSG.io would be helpful.

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    CTS plugin is used by setting the vector layer editable and then selecting source and target CRS codes. – user30184 Sep 24 '17 at 7:45
  • Thanks @user30184! Now I got it. The plugin menu stayed grey until a layer is set to editable. Thanks again! – Kazuhito Sep 24 '17 at 8:15
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    Remember that it is not any on-the-fly function. If you save the layer with the same name original data are overwritten. – user30184 Sep 24 '17 at 9:06

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