Hello,
You can also use the keyword BOTTOM TOPOGRAPHY FILE, which is (hopefully)detailed in the documentation. It allows to interpolate the bathymetry on your mesh, starting from a cluster of points (scalar mode only).
The interpolation is a heavy procedure, but you can do that only once. As a matter of fact, if you do a run with a single time step with the bottom topography as variable for the graphic printouts (
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, you can use this one record result file as a new geometry file that will contain the bottom, and you can remove the BOTTOM TOPOGRAPHY FILE.
With best regards,
Jean-Michel Hervouet