[GAP Forum] [ gauss ] Transposing over GF(2)

[Anvita]

Also, GAP does not seem to be able to properly transpose sparse matrices
over GF(2). I know that such matrices can be treated using a special
compact representation. However, in my opinion this should not mean that
the user must write a new code to deal with this case separately,
especially when the program is expected to work over arbitrary fields.

gap> LoadPackage("gauss");
────────────────────────────────────────────────────────────────
Loading  Gauss 2017.06.14 (Extended Gauss functionality for GAP)
by Simon Goertzen (http://wwwb.math.rwth-aachen.de/goertzen).
Homepage: http://homalg-project.github.io/homalg_project/Gauss/
────────────────────────────────────────────────────────────────
true

gap> ring := GF(3);;
gap> M:=SparseMatrix( 1, 1, [ [ 1 ] ], [ [ One(ring) ] ], ring );;
gap> TransposedSparseMat(M);
<a 1 x 1 sparse matrix over GF(3)>

gap> ring := GF(2);;
gap> M:=SparseMatrix( 1, 1, [ [ 1 ] ], [ [ One(ring) ] ], ring );;
gap> TransposedSparseMat(M);
Error, Record: '<rec>.entries' must have an assigned value in
  Add( T!.entries[M!.indices[i][j]], M!.entries[i][j] ); at
/usr/local/lib/gap4r8/pkg/Gauss-2017.06.14/gap/SparseMatrix.gi:495 called
from
<function "unknown">( <arguments> )
 called from read-eval loop at line 237 of *stdin*
you can 'return;' after assigning a value
brk>