Calculating slope between 5 and 10 percent using raster calculator of QGIS?

Question

I went to Raster --> Analysis --> DEM (Terrain Models) to compute slope.

The slope ranges from 0-39.2311.

Now I'm unsure of the correct way to calculate slope between 5-10% in the raster calculator.

Answer 1

The definition is:

slope[percent] = tan(slope[degree])*100

but, Raster Calculator uses radians instead of degrees for trigonometric calculations. For this reason you have to use:

slope[percent] = tan((slope[degree]*3.141592653589793)/180)*100

Afterward, to select only slope percentages between 5-10% in the Raster Calculator, the expression it would be:

(("slope_percent@1" >= 5.) AND ("slope_percent@1" <= 10.))* "slope_percent@1"