RASTER type datum (ESRI GRID format), consisting of square cells with sides of 10m. The direction of flow expresses the direction in which the surface water flow flows starting from the cell in question, assuming the impermeable slope. In this case the calculation method used is D-Infinity (Dinf. of Tarboton, 1997), according to which, unlike other methods such as D8 (see flow_dir_d8), there are infinite possible directions of flow, corresponding to any direction in the arc of 360°. The D-Infinity (Dinf. of Tarboton, 1997) is one of the most accredited among the so-called "Flow Tracking" methods. It is able to model not only the accumulation of flow in concave areas but also its dispersion in convex ones. The shape of the resulting flow accumulation is therefore much more "natural" and less angular than the one obtained with the D8 method (the only basic content in ArcView/ArcGIS so far). Furthermore, it is not significantly affected by the orientation of the DEM on the territory (any rotations of the grid cause modest variations in the result). The unit of measure is [°sessag.].
