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.
raster_analysis.qgs
).analysis.qgs
).suitable_terrain.shp
dataset.exercise_data/residential_development/
new_solution.shp
which contains
only those buildings which intersect the suitable_terrain
layer.You should now have a layer showing certain buildings as your solution, for example:
Note
If you find that the 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 shapefile with the required CRS. In our
example, the suitable_terrain
layer was reprojected to
WGS 84 / UTM 34S
and named suitable_terrain_34S
.
Look at each of the buildings in your new_solution layer. Compare them with the suitable_terrain layer by changing the symbology for the 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 suitable_terrain layer? Why or why not? Which ones would you deem to be unsuitable?
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 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.
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.
Next you will present these results as part of your second assignment.