.. only:: html |LS| Combining the Analyses =============================================================================== Using the vectorized results of the raster analysis will allow you to select only those buildings on suitable terrain. **The goal for this lesson:** To use the vectorized terrain results to select suitable plots. |moderate| |TY| ------------------------------------------------------------------------------- * Save your current map (:kbd:`raster_analysis.qgs`). * Open the map in which you created during the vector analysis earlier (you should have saved the file as :kbd:`analysis.qgs`). * In the :guilabel:`Layers` panel, enable these layers: * :guilabel:`hillshade`, * :guilabel:`solution` (or :guilabel:`buildings_over_100`) * In addition to these layers, which should already be loaded in the map from when you worked on it before, also add the :kbd:`suitable_terrain.shp` dataset. * If you are missing some layers, you should find them in :kbd:`exercise_data/residential_development/` * Use the :guilabel:`Intersect` tool (:menuselection:`Vector --> Geoprocessing Tools`) to create a new vector layer called :kbd:`new_solution.shp` which contains only those buildings which intersect the :kbd:`suitable_terrain` layer. You should now have a layer showing certain buildings as your solution, for example: .. image:: img/new_solution_example.png :align: center .. note:: If you find that the :guilabel:`Intersect` tool does not produce any results, check the CRS settings of each of your layers. The CRS must be the same for both the layers you are comparing. You may need to reproject one layer by saving the layer as a new file with the required CRS. In our example, the :file:`suitable_terrain` layer was reprojected to |localCRS| and named :file:`suitable_terrain_34S.shp`. .. _backlink-complete-analysis-2: |moderate| |TY| Inspecting the Results ------------------------------------------------------------------------------- Look at each of the buildings in your :guilabel:`new_solution` layer. Compare them with the :guilabel:`suitable_terrain` layer by changing the symbology for the :guilabel:`new_solution` layer so that it has outlines only. What do you notice about some of the buildings? Are they all suitable just because they intersect with the :guilabel:`suitable_terrain` layer? Why or why not? Which ones would you deem to be unsuitable? :ref:`Check your results ` .. _backlink-complete-analysis-3: |moderate| |TY| Refining the Analysis ------------------------------------------------------------------------------- You can see from the results that some buildings which were included were not really suitable, so we can now refine the analysis. We want to ensure that our analysis returns only those buildings which fall entirely within the :kbd:`suitable_terrain` layer. How would you achieve this? Use one or more Vector Analysis tools and remember that our buildings are all over 100m squared in size. :ref:`Check your results ` |IC| ------------------------------------------------------------------------------- You have now answered the original research question, and can offer an opinion (with reasons, backed by analysis) for a recommendation regarding which property to develop. |WN| ------------------------------------------------------------------------------- Next you will present these results as part of your second assignment. .. Substitutions definitions - AVOID EDITING PAST THIS LINE This will be automatically updated by the find_set_subst.py script. If you need to create a new substitution manually, please add it also to the substitutions.txt file in the source folder. .. |IC| replace:: In Conclusion .. |LS| replace:: Lesson: .. |TY| replace:: Try Yourself .. |WN| replace:: What's Next? .. |localCRS| replace:: ``WGS 84 / UTM 34S`` .. |moderate| image:: /static/global/moderate.png