Simultaneous editing and multilabelling of graphs in system newGraph

In our research in spectral graph theory we often encounter the need for the simultaneous editing of two or more interdependent graphs (e.g. a graph and its line graph), together with multiple labellings of their vertices and edges. Occasionally, labellings are of such kind that it could be beneficial to permit the user to modify the labelling and test whether it still satisfies a given property. Here we develop a methodology for treating such situations, which is implemented in system newGRAPH.