[Qgis-user] Marxan for QGIS
Hello, I am writing to ask for some technical support. I am currently trying to use Marxist to create a Marine Spatial Plan for my PhD thesis, this will be the first MSP for our Marine Protected Area. I am using version 3.32.3 of QGIS and when I launch Marxan from the CLUZ plug in, it's keeps saying program now responding. I used CLUZ for all other stages and it worked fine. Can you give me any suggestions to overcome this problem? Is the version of QGIS? Any assistance would be greatly appreciated. Thank you. Kind regards, Shivonne M. Peters Get Outlook for Android<https://aka.ms/AAb9ysg> ___ QGIS-User mailing list QGIS-User@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Bathymetry data area coverage calculator
Thanks, I'll check it out. On Sat, Jul 31, 2021, 20:42 Charles Dixon-Paver wrote: > The raster calculator is a tool for raster analysis which doesn't quite > suit your needs as I understand them. If you want to learn how to use the > raster calculator there is a tutorial available on the QGIS changelog > lessons [1]. > > That blog post I linked to before is likely the most effective or > performant option for you, and it contains links to scripts that will > perform the analysis for you. > > As an alternative, I have created a simple model which steps through the > vectorization process of reclassifying a raster and calculating the area > [2]. The data I used to test the model was the SRTM tile used in the > previously mentioned lesson [1], so you can introspect it and copy the > logic or tweak it as needed. I did a session on using the modeler for the > last Open Day [3] so you can get familiar with them if you aren't already. > > [1] https://changelog.qgis.org/en/qgis/lesson/raster-16/detail/51/?q=7.2 > [2] > https://github.com/zacharlie/effective-dollop/blob/main/qgis-models/raster_area_calculation_example.model3 > [3] https://github.com/qgis/QGIS/wiki/QOD-July-2021 > > On Sat, 31 Jul 2021 at 20:29, Peters wrote: > >> Very helpful. Yes, our data is raster. I saw a calculator tool in the >> raster toolbar but haven't been able to figure it out or if it's pertinent. >> >> On Sat, Jul 31, 2021, 19:01 Charles Dixon-Paver >> wrote: >> >>> I think you will need to provide more information on describing the >>> input data, as well as how exactly you wish to process it. >>> >>> If your coverage data is vector areas you should be able to simply use >>> the aggregate processing tool using $area as the source expression and >>> stipulate a sum aggregate function. You may also use the grouping >>> function to filter the results as needed using an expression. >>> >>> This would provide the area based on map units, so you would need to >>> reproject your data into a relevant metric projection before performing the >>> aggregation. A single hectare is simply 1 m² so simple arithmetic will >>> allow you to convert metric areas to hectares. >>> >>> If your data is another vector data type such as point clouds, you may >>> need to buffer or calculate a minimum bounding geometry or convex hull >>> before processing it as the area calculation will of course only work on >>> area features. >>> >>> For raster data, the total area would be a simple calculation of the >>> extents, or the dimensions and cell size. Again, you may need to reproject >>> the data for it to be available in meters. >>> >>> If, however, you wish to segregate raster data based on cell value, you >>> may want to recode and vectorize the data, or alternatively perform some >>> form of custom analysis as described in the following article: >>> https://www.kartoza.com/en/blog/calculating-area-of-rasters-in-qgis/ >>> >>> Regards >>> >>> On Sat, 31 Jul 2021 at 19:15, Peters wrote: >>> >>>> Does anyone know of such a calculator as a plugin or option? At the >>>> moment I am using QGIS app. Our client has asked for area coverage in sq. >>>> mtrs or hectares. Appreciate any info you may have. >>>> >>>> -- >>>> *regards,* >>>> *K. Peters* >>>> >>>> *cell: (Morocco) +212.671.218606* >>>> ___ >>>> Qgis-user mailing list >>>> Qgis-user@lists.osgeo.org >>>> List info: https://lists.osgeo.org/mailman/listinfo/qgis-user >>>> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user. >>>> >>> ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Bathymetry data area coverage calculator
Very helpful. Yes, our data is raster. I saw a calculator tool in the raster toolbar but haven't been able to figure it out or if it's pertinent. On Sat, Jul 31, 2021, 19:01 Charles Dixon-Paver wrote: > I think you will need to provide more information on describing the input > data, as well as how exactly you wish to process it. > > If your coverage data is vector areas you should be able to simply use the > aggregate processing tool using $area as the source expression and > stipulate a sum aggregate function. You may also use the grouping > function to filter the results as needed using an expression. > > This would provide the area based on map units, so you would need to > reproject your data into a relevant metric projection before performing the > aggregation. A single hectare is simply 1 m² so simple arithmetic will > allow you to convert metric areas to hectares. > > If your data is another vector data type such as point clouds, you may > need to buffer or calculate a minimum bounding geometry or convex hull > before processing it as the area calculation will of course only work on > area features. > > For raster data, the total area would be a simple calculation of the > extents, or the dimensions and cell size. Again, you may need to reproject > the data for it to be available in meters. > > If, however, you wish to segregate raster data based on cell value, you > may want to recode and vectorize the data, or alternatively perform some > form of custom analysis as described in the following article: > https://www.kartoza.com/en/blog/calculating-area-of-rasters-in-qgis/ > > Regards > > On Sat, 31 Jul 2021 at 19:15, Peters wrote: > >> Does anyone know of such a calculator as a plugin or option? At the >> moment I am using QGIS app. Our client has asked for area coverage in sq. >> mtrs or hectares. Appreciate any info you may have. >> >> -- >> *regards,* >> *K. Peters* >> >> *cell: (Morocco) +212.671.218606* >> ___ >> Qgis-user mailing list >> Qgis-user@lists.osgeo.org >> List info: https://lists.osgeo.org/mailman/listinfo/qgis-user >> Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user. >> > ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] Bathymetry data area coverage calculator
Does anyone know of such a calculator as a plugin or option? At the moment I am using QGIS app. Our client has asked for area coverage in sq. mtrs or hectares. Appreciate any info you may have. -- *regards,* *K. Peters* *cell: (Morocco) +212.671.218606* ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] Export GeoPDF Mac
Hi Adam, I was also interested in this capability, but hit the following roadblock - which I would be grateful if anyone can help resolve: The GDAL version (2.4.1) that comes packaged with the all-in-one installer for Mac (for QGIS 3.12, 3.10. 3.4) apparently can’t support GeoPDF creation, yet I could find no source for the more current GDAL version (3.0+) that is needed. It appears this newer version is available for non-Mac installs, but not yet for Mac. Anyone know differently? This effectively seems to mean that in fact GeoPDF creation is not currently supported for Mac installs. Depending on your needs you may find exporting to Geotiff (which does work on Mac) as a viable alternative, though it creates larger files. For instance, if you want the GeoPDF (geospatial PDF=not the same thing) for use in a mobile mapping app like Avenza, then the Geotiff is a workable alternative - just make sure to check the box to export the associated world file and then bundle this with the tiff in a Zip before importing to Avenza. Here are a couple related threads, but unfortunately there seems to be no resolution yet: https://gis.stackexchange.com/questions/345761/export-geospatial-pdf-from-qgis-on-mac <https://gis.stackexchange.com/questions/345761/export-geospatial-pdf-from-qgis-on-mac> https://gis.stackexchange.com/questions/354383/updating-gdal-to-3-0-from-2-4-1-on-mac-to-create-geopdfs-in-qgis-3-10 <https://gis.stackexchange.com/questions/354383/updating-gdal-to-3-0-from-2-4-1-on-mac-to-create-geopdfs-in-qgis-3-10> Hope this gets resolved in coming versions, it sure would be nice for Mac users to have access this functionality. Best, Matt Peters > > Message: 1 > Date: Sat, 16 May 2020 00:02:27 +0100 > From: Adam Sneath > To: qgis-user@lists.osgeo.org > Subject: [Qgis-user] Export GeoPDF Mac > Message-ID: <97c62762-16f4-441d-ae58-271d78033...@gmail.com> > Content-Type: text/plain; charset="utf-8" > > Hello there. I want to export a georeferenced PDF from my QGIS project, and I > am unable to tick the box as I need GDAL 3.0. However, my colleague is using > windows (I am using a mac) and he is able to export as a GeoPDF without any > issue, despite him not having GDAL. I hoped you could help me towards a > solution. Thanks > -- next part -- > An HTML attachment was scrubbed... > URL: > <http://lists.osgeo.org/pipermail/qgis-user/attachments/20200516/9f383df1/attachment-0001.html> > > -- > > Message: 2 > Date: Sat, 16 May 2020 11:07:46 +0200 > From: Andreas Neumann > To: qgis-user@lists.osgeo.org > Subject: Re: [Qgis-user] Export GeoPDF Mac > Message-ID: <421d2695-e6be-6ec4-86c8-212b5fb41...@carto.net> > Content-Type: text/plain; charset="windows-1252"; Format="flowed" > > Hi Adam, > > GDAL is an integral part of QGIS. QGIS doesn't work without GDAL. So I'm > 100% sure that your colleague on Windows also has GDAL. Maybe you just > aren't aware of it. If you go to the about screen in the help menu. What > does it say there about GDAL? On your Mac and on the Windows > installation of your colleague? > > Also: what QGIS version do you use on the Mac? GeoPDF is relatively new > and you need both a new GDAL and a new QGIS. But normally you don't have > to worry about GDAL. If you use the new MacOS all in one installer, GDAL > should be installed automatically with it. With the older way of > installing QGIS on the Mac you still had to install it separately. Both > approaches have advantages/disadvantages. > > Greetings, > > Andreas > ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
