For the Leibniz Institute for Freshwater Ecology and Inland Fisheries, we have converted their GRASS GIS-based fish dispersion model (FIDIMO) from raster to vector data. For this it was necessary to carry out river network analyzes with GRASS GIS (e.g .: the calculation of the radiator flow order) based on a vector network. The order of the rivers, as can be seen in the figure, is stored in the attribute table of the result vector map.
From GRASS GIS 7.1 the v.stream.order module is now available. This is the implementation of the original Emitter and Shreve algorithms based on vector line networks. Part of the implementation was also the implementation of unit tests as well as the generation of test data that reflect the specific properties of the networks. The unit tests have been integrated into the GRASS GIS test framework.