Exploring numeric value distribution in a column
In this recipe, we will look at how to explore the properties of a column of numeric values. We will look at the tools that QGIS offers and apply them to analyze the elevation values in our sample POI dataset.
Getting ready
To follow this recipe, please load poi_names_wake.shp. If you followed the previous recipe, Listing unique values in a column, you can continue directly from there.
How to do it…
A good way to get a first impression of the properties of a numeric column is using the Basic Statistics tool from Vector. This allows you to calculate statistical values, such as the minimum and maximum values, mean and median, standard deviation, and sum.
If you want to examine the distribution of elevation values, there is the handy Statist plugin. Statist generates an interactive histogram representation of the value distribution:
Install Statist using Plugin Manager.
Start Statist from the Vector menu.
Specify Input vector layer and the attribute...
