Extending Isomorphisms


My goal is to write a script which checks if it is possible
if there is an extension from an isomorphism between two
subgraphs of one graph, say G, to an automorphism on G.

Problemetic is that if i check for the isomorphisms than iGraph
destroys the numbering of vertices, i.e. it resets the indexing
back to 0 and increments with each new vertex.

Why do I need that? I thought about embedding the isos into
the automorphisms but for this the indexing should coincide…

Any ideas how to fix this, or how to tackle this problem?

Some technical notes: I was using Python and the usual commands like

I find it difficult to follow the question. It’s not clear to me what you mean by “extension”. Can you clarify and include a concrete example of what you need as output?