Yes, the HUGIN GUI allows the user to save and load structural constraints between nodes in a file. Structure constraints can be saved in and loaded from a file in the “Structure Constraints”-step of the Learning Wizard. You use the “save network with constraints” button to save structure constraints in a network specification file and the “import model information” button to load constraints from a network specification file.
For instance, if you want to disallow a certain direction on a link, then you would use the “No Arrow Constraint Tool” to define a constraint that a node X is not allowed to be parent of node Y. You can add multiple constraints in one operation by selecting a set of nodes and pressing the right mouse button on another node.
The constraints are saved in a HUGIN .net file. This file can be loaded into the “Structure Constraints”-step of the Learning Wizard. The constraints are defined as attributes on nodes in the .net file. For instance, the “HR_Constraint_X” attribute of this node definition of node D in a .net file:
node D
{
label = "D";
position = (210 110);
states = ("yes" "no");
HR_Constraint_X = "NoArrow";
}
Specifies that node D is not allowed to be a parent of X.