Hi! I am not sure how you are generating the resistance file, but there are only 2 ways for MIKE 21 to read it, either a dfs2 or a dfsu file. In the case of the dfs2 it is straight forward to change the values manually, you just open the dfs2 file and enter the desire values manually. With the toolbar you can even select a number of grids and change all the values at once for those areas. You can also delete them and use the interpolation tool to fill in the map. If you are using a dfsu file, you can also use the toolboxes to select several elements and then "calculate" the new value. You can see the manuals for the dfs2 and dfsu files for more info. If you try it and get in problems please provide more details!

Well described by Christian

Hello,

Thank you very much for answer :)

Actually I use dfs2 file to prepare resistance. My problem is that Mike see artificial minus vlues within a grid cells. I tried to select them (using "select" tools) and change the values but it dosen't work. In basic raster, minus values don't occur, thus I don't know how to fix it.

Best,

Ewelina

Actually I think there is a problem with values type in basis raster and NoData values.

Sorry! I am using Mike 21 SW but i do not understand parameter "Directional stander deviation" in boundary conditions. I hope you can help me! Thanks you!!

Please remember that the MIKE 21 SW model is a spectral wave model, that means that even if you provide your boundaries as wave parameters, there wave direction has some dispersion, and it can be assess either by the standard deviation from the main wave direction (which in fact ADCPs calculate such parameter based on the measurements) or as a spectral shape (you can see that on the scientific documentation of the model). If you have an area dominated by swell, probably the directional standard deviation is small (smaller than 30 degrees), but if your area is dominated by seas, then your directional standard deviation is large (larger than 30 degrees). Hope this helps!