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I have looked through the online documentation for CUDD (http://web.mit.edu/sage/export/tmp/y/usr/share/doc/polybori/cudd/cuddIntro.html), a library for Binary Decision Diagrams (BDDs) but could not find a method for turning off the automatic use for complement edges for BDDs. It does seem to me it should exist, do you know whether it exists?

Daniel Miedema
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This functionality does not exist in CUDD as the use of complemented edges is implemented as non-optional feature in every single BDD manipulation function.

It is also unclear what use it would have. The functionality of CUDD is not altered by switching off complemented edges. If your interest is to not have complemented edges show up in visualizations of BDDs, it would make more sense to write a visualization function that distinguishes between complemented and non-complemented nodes, which is possible (and has been done before) and gets rid of the complemented else edges.

DCTLib
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  • Hey thanks for answering, i need it for testing sizes of BDDs without complement edges. I will have to find a work around then in my research project.. – Daniel Miedema Nov 25 '21 at 12:18
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    @DanielMiedema Perhaps there is indeed an easy workaround. It's not difficult to build your own function for counting the number of nodes of a BDD that considers nodes and complemented nodes separately so that if a node appears complemented and non-complemented, it counts as two nodes. Note, however, that the variable reordering heuristics may work a bit different in the case of having complemented else-edges as they will trigger reordering at different times (and perhaps optimize slightly differently). – DCTLib Nov 25 '21 at 20:09