INT,<n1>,<n2>,[<inc>],<set>,[<code>]

sets interaction, intermediate, interface, or internal nodes. The node set is defined by start node number <n1>, end node number <n2>, and step <inc>. Depending on the value of parameter <set>, this instruction sets (<set>=1) or resets (<set>=0) the nodes as interaction (<code>=0), intermediate (<code>=1), interface (<code>=2), or internal (<code>=3).This instruction is used after the nodes have been previously defined.