November 2018
Beginner to intermediate
272 pages
5h 36m
English
Content preview from Learn QGIS - Fourth Edition
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Creating a heatmap from points
In Chapter 3, Visualizing Data, we showed how points can be symbolized on the fly as a Heatmap. Now, let's take a look at how to create a Heatmap and save it as a permanent raster dataset. In the processing toolbox, search for Heatmap and double-click on the corresponding result: Heatmap (Kernel Density Estimation).
Complete the dialog box as shown as follows with a kernel radius of 300,000 layer units, which, in the case of our airport data, is displayed in feet. In QGIS 3.4, you can adjust the measurement unit in the tool, so, if you prefer, you could calculate in meters. I have set the pixel size to 10000 by 10000:
Heatmap dialog box
Radius determines the distance around each point at which the point will ...
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