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In QGIS, if I have some nodes with a name attribute is there a way to display only one node that would be in the middle of this group of nodes having the same name?

For example, let's say i have 3 nodes with an attribute "ABC" I would like to display one node what would be in the middle of this group.

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A static solution would be to use Vector-->Geoprocessing tools-->Convex hull(s); Select 'Create convex hulls based on input values' and select your attribute field; Then change the style of the polygons to 'Centroid field', or create centroids from the polygons. The latter option is one extra step, but will probably give you better options for labeling.

If you need a dynamic solution, I beleive this could be handled py postGis or spatiaLite pretty easily.

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Thank you for your answer but it's not working exactly like what I was waiting for.

If i filter them by the name attribute, let's say create a Convex hull withe all the nodes having the same name, it will create those Convex hulls, but it will not keep attributes, not even the name, and then creating centroid fields i only get a few nodes not corresponding at all with the nodes areas I already have.

I will ask a friend of mine if he know a SQL command for this to make a rule based rendering directly in QGIS.

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