Spatial Analysis of Accessibility of Wells using Map Algebra
3. Condition 1: Wells within 150 Meters of Houses or Roads
3.1. Style a discrete raster layer
Let's first look at the houses. The houses are a class in the buildg layer. Rasters normally only store values, so we need to assign a proper legend to raster layers.
1. In the Layers panel click on the 
to open the Layer styling panel.
2. Choose Paletted/Unique values as render type. Keep Random as Color ramp type and click Classify.
3. Use the screenshot below as a reference to add the labels to the class numbers by double-clicking on each label name. Double-click on the color to make it more intuitive as shown in the example.
Because buildg is a discrete raster we used the Paletted/Unique values render type. This renderer classifies each unique integer value found in the raster layer.