To edit boundary conditions, click in menu *Hydraulics > Boundary conditions*.
The window contains a table with the list of boundary conditions and a view of the study river network.
A boundary condition is defined by this name, this type of boundary condition and an associated node.
:warning: If you **change the type** of boundary condition with some data, **you must lose this data**. (:bulb: You can cancel the previous action with Ctrl + Z)
To edit a boundary condition click on edit button ![edit](https://gitlab.irstea.fr/theophile.terraz/pamhyr/-/raw/master/src/View/ui/ressources/edit.png){height=20px}, a new window will appear. In this window, you see a table with two columns and a plot with these two columns on the two axes. The type of these two columns can change with the type of boundary conditions. You can add and delete values and sort the table values.