ElationOfProjectiveSpace panics in PG(n, F), with char(F) = 2.

Hi,

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I’m trying to use ElationOfProjectiveSpace to construct some elations in PG(n, q), with q = 2^k. I keep running into issues where this function will panic. It seems specific to characteristic two fields, as I could not reproduce the behaviour with the example in the docs, and the backtrace on the error involves CONV_GF2VEC.

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Here is some minimal code that reproduces my example:

ps := PG(2, 8);;
l := HyperplaneByDualCoordinates(ps, [1, 0, 0] * Z(2)^0);;
p := VectorSpaceToElement(ps, [1, 0, 0] * Z(2)^0);;
q := VectorSpaceToElement(ps, [1, 1, 0] * Z(2)^0);;
psi := ElationOfProjectiveSpace(l, p, q);

This produces the following error:

Error, Panic: cannot convert <list> (is a data object) to a plain list in
  CONV_GF2VEC( v ); at /usr/lib/gap/lib/vecmat.gi:1370 called from 
ConvertToVectorRepNC( vc, f ); at /usr/lib/gap/lib/matrix.gi:2358 called from
SemiEchelonMat( gens ) at /usr/lib/gap/lib/vspcrow.gi:747 called from
BasisVectors( Basis( ComplementSpace( vssub, [ e0 ] ) ) ) at /usr/lib/gap/pkg/fining/lib/projectivespace.gi:2434 called from
<function "ElationOfProjectiveSpace for a hyperplane and two points of the same projective space">( <arguments> )

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If it’s relevant, I am running the latest version of GAP (4.11.1) and FinInG (1.4.1), on Linux.

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