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I am trying to measure the distance from several points to the edge of lake polygons. When I use the Distance to Nearest hub function in Vector analysis, I get the following error message:

QGIS version: 3.30.0-'s-Hertogenbosch
QGIS code revision: f186b8efe0
Qt version: 5.15.2
Python version: 3.9.5
GDAL version: 3.3.2
GEOS version: 3.9.1-CAPI-1.14.2
PROJ version: Rel. 8.1.1, September 1st, 2021
PDAL version: 2.3.0 (git-version: Release)
Algorithm started at: 2023-03-23T23:45:14
Algorithm 'Distance to nearest hub (line to hub)' starting…
Input parameters:
{ 'FIELD' : 'Hylak_id', 'HUBS' : '/Users/user/Downloads/HydroLAKES_polys_v10_shp/HydroLAKES_polys_v10_shp/HydroLAKES_polys_v10.shp', 'INPUT' : 'delimitedtext://file:///Users/user/Documents/Grebe_Population_Points.csv?type=csv&maxFields=10000&detectTypes=yes&xField=Longitude&yField=Latitude&crs=EPSG:4326&spatialIndex=yes&subsetIndex=no&watchFile=no', 'OUTPUT' : 'TEMPORARY_OUTPUT', 'UNIT' : 0 }

Traceback (most recent call last):
File "/Applications/QGIS.app/Contents/MacOS/../Resources/python/plugins/processing/algs/qgis/HubDistanceLines.py", line 120, in processAlgorithm
index = QgsSpatialIndex(hub_source.getFeatures(QgsFeatureRequest().setSubsetOfAttributes([]).setDestinationCrs(point_source.sourceCrs(), context.transformContext())))
Exception: unknown

Execution failed after 0.13 seconds

Loading resulting layers
Algorithm 'Distance to nearest hub (line to hub)' finished

What am I doing wrong? Is there a different function I should be using?

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  • 1
    Are your layers projected ? See gis.stackexchange.com/questions/304010/…
    – Kasper
    Mar 24, 2023 at 6:19
  • It's going to be hard to diagnose an Unknown Exception without more information. However, keep in mind that Distance to Nearest Hub calculates the distance to the centre of a polygon, not the edge of the polygon, so it doesn't sound like it's going to be the solution to your problem. Mar 24, 2023 at 6:41
  • 1
    This answer may help you: gis.stackexchange.com/a/447505/128665. It uses a Field Calculator expression, rather than the Distance to Nearest Hub tool.
    – Matt
    Mar 24, 2023 at 8:41

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