Logic is a mode whereby object relationships are enforced. When turned on, NetPoint will heal a negative-gap link as it forms to preserve the logic of the original relationship. For example, if an activity is moved earlier in time, NetPoint will move any zero-gap predecessors along with the activity in real-time (until reaching an actualized object or constraint). Additionally, if the activity has any zero-gap successors, they will be moved earlier to maintain the zero-gap link (unless they were actualized or constrained).
Likewise, if an activity is moved later than in time, NetPoint will move any zero-gap successors later along with the activity (until reaching an actualized object or constraint). In this case, however, all predecessors will remain fixed, even if connected by a zero-gap link, allowing the activities to break open. The same rules also apply when crashing or extending an activity’s duration. In short, logic mode will propagate a change throughout a network. Without logic mode on, a change will be localized to the affected object itself.
This process by which predecessors and successors are moved automatically is known as self-healing. By default, logic mode is turned on but can be turned off if desired. It is helpful to save the plan before using this option.
NOTE: If a milestone is assigned a calendar that’s different from that of its predecessors or successors, and the network is pulled backwards, gaps may open up as the chain crosses a weekend or non-working days, despite logic being on. As such, it is recommended to always keep milestones on the same calendar as their predecessors/successors.
- Click the Logic Mode icon in the toolbar.
- Adjust the network as desired.
- When finished, turn Logic Mode back on.
NOTE: Negative-gap links will not be corrected by the system until Logic Mode is turned back on and one or more of the activities impacting these links are moved (either the predecessor or successor of the link with negative-gap or an activity which falls on the same path as the link with negative-gap).
NetPoint does not allow an activity to have the same activity as a predecessor and successor (or in the predecessor and successor chains (for example, activity A linked to activity B, linked to activity A). This is known as a logic loop. However, it is still possible to open a schedule that was created before loops were prohibited. In this case, a window will open, the links in the logic loop will be highlighted, and one of the links must be deleted before proceeding. If multiple loops are present, the window will open for each loop.