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To edit a variable, either select it and then click the 'pencil and paper' icon, or right-click the variable and choose 'Edit variable' from the context menu. A shortcut is to double-click the variable. A simple dialogue allows for the modification of the variable's value:
If the name of the variable is changed, a new variable will be created and the old one will remain.
It is important to understand what happens when editing a variable inherited from higher in the hierarchy. In this case, the ancestor node is not modified, but a duplicate of its variable is created at the level of the selected node.
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