Differences between terrain fluctuations and slopes

Terrain fluctuations refer to the difference between the highest point and the lowest point in a specific area.
The slope is the steep degree of the surface unit. The ratio of the direct height h and the horizontal width l of the slope is usually called the slope.
1) Activate DEM data and use grid neighborhood statistics in spatial analysis. Set statistic type to the maximum value, and the type of the adjacent area to a rectangle (or a circle). Set the size of the adjacent area according to your own needs, you can get a maximum level, which is counted as;
2) Repeat steps 1 and 2. Set the statistic type value to the minimum value to obtain the minimum level of DEM data, which is recorded as B;
3) use the raster calculator in spatial analysis. The formula is [a]-[B] to obtain a new level, the value of each grid is the terrain Fluctuation value in the definite neighborhood centered on the grid.

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