[Qgis-user] Calculate upslope catchment areas for multiple points?

[kirk]

Hi Ben.The python script should work in your version since it is written in python 3.  It us,a relatively simple routine which iterates over each sample point and rund the saga tool.  It nay take a while to run 100s of points but it should finish.Saga is a third party, open source software suite that is developed independantly of QGIS.  It is very powerful and fast for most raster processing.  Saga also has native batch or scripting capability which may be an option for you.  Just a note that the module syntax can change  with versions. So and older script may not complete on a new release.Kirk SchmidtSent from my Galaxy
-------- Original message --------From: Ben Jones via QGIS-User <qgis-user at lists.osgeo.org> Date: 2024-01-14  2:23 a.m.  (GMT-04:00) To: Qgis <qgis-user at lists.osgeo.org> Subject: [Qgis-user] Calculate upslope catchment areas for multiple points? Hello All,I have used SAGA to generate channel networks and r.watershed to generate catchment sub-basins from Copernicus 30 m DEM data to assist with planning a stream sediment sampling program. Once samples are collected I would like to generate polygons that define the upslope area for each sample point.I understand that this can be done using SAGA Terrain Analysis ‘Upslope area’ tool that requires manually copying and pasting the X and Y coordinates for each sample point (one point at a time which works but is not practical for 100’s of samples, or in batches which is still not ideal and doesn’t appear to work?).Is there an easy way to import a point file with multiple points (100’s of points) to SAGA or another tool to automatically calculate upslope catchment areas for each of the points?I have come across two potential solutions:1) ‘Qgis SAGA Upslope Area for several points automation’:https://gis.stackexchange.com/questions/342333/qgis-saga-upslope-area-for-several-points-automation2) ‘Snap pour points and delineate multiple catchments in QGIS’:https://www.youtube.com/watch?v=Hqc_1CMadhAHowever, both are three years old and it appears there are complications using both these methods in newer versions of QGIS3. Are there alternative methods?I am using QGIS 3.28.11a on macOS Monterey.Thanks,Ben_______________________________________________QGIS-User mailing listQGIS-User at lists.osgeo.orgList info: https://lists.osgeo.org/mailman/listinfo/qgis-userUnsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osgeo.org/pipermail/qgis-user/attachments/20240114/7b593769/attachment.htm>