Generalizing the geometry, also known as simplifying, removes points from a vector layer to reduce the space required to store the data on disk, the bandwidth needed to move it over a network, and the processing power required to perform analysis with it or display it in QGIS. In many cases, the geometry of a layer contains redundant points along with straight lines that can be removed without changing the spatial properties of a layer, with the exception of topology constraints.
For this recipe, we will use a boundary file for the state of Mississippi, which you can download from https://geospatialpython.googlecode.com/files/Mississippi.zip.
Extract the zipped shapefile to a directory named /qgis_data/ms
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