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thetensor-space / Auto-Sandbox

Algorithms for automorphism groups
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Crash in AutomorphismGroupByInvariants #11

Closed eamonnaobrien closed 5 years ago

eamonnaobrien commented 5 years ago

G:= PCGroup([ 9, -11, 11, 11, 11, 11, -11, 11, 11, 11, 27041107303, 526156886, 395615, 701542524, 527493, 79780153, 79725712 ]);

AutomorphismGroupByInvariants (G) crashes with error In file "/home/eobr007/Stabiliser/Auto-Sandbox/src/isom-test.m", line 271, column 11:

LV := L @ piV; ^ Runtime error in map application: Element is not in the domain of the map

Indeed L is not in the domain of the map. I believe the source of the error is the following change to the defn of Subgroup in isom-test.m. The filler might more sensibly be to define Subgroup as the trivial group of the domain -- but IsometryGroup doesn't help!

try vprint Autotopism, 1 : "Adding exponential of derivations by Brooksbank-Maglione-Wilson."; // Subgroup := ExponentiateDerivations(T); Subgroup := IsometryGroup(T); // No more ExponentiateDerivations. I Put this in as filler. -Josh catch e vprint Autotopism, 1 : "Lie algebra methods not fully supported for this tensor";//, e;

algeboy commented 5 years ago

The filler was indeed wrong. It is the right group but not acting on the whole space. It needs to be padded out with the identity to be a subgroup of the pseudo-isometry group. I added this and it now works.