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Bug introduced in 10.3.1 or earlier and fixed in 11.2.0
This bug was specific to the Raspberry Pi version.


I am using Mathematica 10.3.1.0 on a Raspberry Pi 3. The following input:

k = Graph[{1, 2}, {UndirectedEdge[1, 2]}];
GraphAutomorphismGroup[k]

returns the output

PermutationGroup[{}]

Shouldn't it return instead, something like this ?

PermutationGroup[{Cycles[{{1,2}}]}]

Perhaps I have misunderstood, or perhaps the graph automorphism group function is not supported on the Raspberry Pi ?

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  • 1
    $\begingroup$ Version 10.3.1 on Mac OS gives PermutationGroup[{Cycles[{{1, 2}}]}] $\endgroup$ – Jason B. Aug 10 '16 at 18:27
  • $\begingroup$ Can you get any of the examples in GraphAutomorphismGroup to work? $\endgroup$ – Jason B. Aug 10 '16 at 18:33
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    $\begingroup$ You should report that to WRI support, regardless if others have reported it. $\endgroup$ – user21 Aug 10 '16 at 20:02
  • $\begingroup$ @JasonB I tried one of those, which also didn't work. $\endgroup$ – Simon Aug 10 '16 at 20:20
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Update: This seems fixed in the latest RPi version, 11.2.0.

This is a bug specific to the Raspberry Pi (or rather ARM versions of Mathematica?). I reported it on February 21, 2016, and Wolfram Support told me that it is a known issue.

A workaround is to use the IGraph/M package, which provides the same functionality and works fine on the Raspberry Pi.

<<IGraphM`

IGBlissAutomorphismGroup[k]

(* {{2, 1}} *)

It returns a list of group generators, which you can use with PermutationGroup to construct a group.

Note: IGraph/M is very slow to load on the RPi. It may take a minute. Update: Since version 0.3, IGraph/M uses lazy loading and is much quicker to load on the Raspberry Pu.

Disclosure: I am the author of IGraph/M (but not of igraph).

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  • $\begingroup$ Thank you very much Szabolcs ! You helped me a while ago with another graphs issue. I installed IGraph/M on the laptop I was using at the time but unfortunately was unable to use it because it wasn't compatible with version 9 of Mathematica. Now that I have an up-to-date version of Mathematica I am very much looking forward to trying IGraph/M ! $\endgroup$ – Simon Aug 10 '16 at 20:28

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