I am going to generate isochrones using the Iso-Area algorithm of the QNEAT3 plugin. I have a CSV file including start point coordinates. I read this file as a layer in QGIS. Then I saved the features of this layer (Let's consider it A) as it is shown in the next picture:
I also downloaded the road network from http://download.geofabrik.de/ and added it as a layer to QGIS. Then I saved this layer (Let's consider it B) as it is shown in the following figure:
Finally, in the Iso-Area as polygon (from layer) parameters tab, I selected B as the input of vector layer representing network and A as the input of stat points. after running the algorithm I got this error:
File "C:/../AppData/Roaming/QGIS/QGIS3\profiles\default/python/plugins\QNEAT3\algs\IsoAreaAsPolygonsFromLayer.py", line 229, in processAlgorithm net = Qneat3Network(network, input_coordinates, strategy, directionFieldName, forwardValue, backwardValue, bothValue, defaultDirection, analysisCrs, speedFieldName, defaultSpeed, tolerance, feedback) File "C:/.../AppData/Roaming/QGIS/QGIS3\profiles\default/python/plugins\QNEAT3\Qneat3Framework.py", line 130, in init self.list_tiedPoints = self.director.makeGraph(self.builder, self.list_input_points, self.feedback) Exception: unknown
there is not any clear message regarding the error that happened. what could be a probable cause of this problem?
The network layer must be in a projected CRS with the LineString geometry type. The start points layer must be in a projected CRS with point geometry type. I downloaded another road network data set and applied the mentioned conversions, then the problem solved
