This tool is used to generate a flow pointer grid (i.e. flow direction) using the D-infinity (Tarboton, 1997) algorithm. Dinf is a multiple-flow-direction (MFD) method because the flow entering each grid cell is routed one or two downslope neighbours, i.e. flow divergence is permitted. The user must specify the name of a digital elevation model (DEM; dem) that has been hydrologically corrected to remove all spurious depressions and flat areas (breach_depressions_least_cost, fill_depressions). DEM pre-processing is usually achieved using the breach_depressions_least_cost or fill_depressions tool1. Flow directions are specified in the output flow-pointer grid (output) as azimuth degrees measured from north, i.e. any value between 0 and 360 degrees is possible. A pointer value of -1 is used to designate a grid cell with no flow-pointer. This occurs when a grid cell has no downslope neighbour, i.e. a pit cell or topographic depression. Like aspect grids, Dinf flow-pointer grids are best visualized using a circular greyscale palette.

Grid cells possessing the NoData value in the input DEM are assigned the NoData value in the output image. The output raster is of the float data type and continuous data scale.

Reference

Tarboton, D. G. (1997). A new method for the determination of flow directions and upslope areas in grid digital elevation models. Water resources research, 33(2), 309-319.

See Also

DInfFlowAccumulation, breach_depressions_least_cost, fill_depressions

Function Signature

def dinf_pointer(self, dem: Raster) -> Raster: ...

Project Links

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