Hello
I have some trouble with Goppa Codes
Here is the problem

gap> x := Indeterminate( GF(2), "x" );;
gap> L := Elements( GF(8) );;
gap> G := x^2+x+1;;
gap> C := GoppaCode( G, L );
Error, no method found! For debugging hints type ?Recovery from
NoMethodFound
Error no 1st choice method found for `CoefficientsRing' on 1 arguments
at
Error( no_method_found );
CoefficientsRing( DefaultRing( p ) ) called from
Codeword( x ^ (i - 1) mod temp, m + 1 ) called from
VerticalConversionFieldMat( M, DefaultField( Flat( M ) ) ) called from
VerticalConversionFieldMat( List( [ 0 .. r - 1 ], function ( i )
return List( L, function ( j )
return j ^ i / Value( GP, j );
end );
end ) ) called from
<function>( <arguments> ) called from read-eval-loop
Entering break read-eval-print loop, you can 'quit;' to quit to outer
loop,
or you can return to continue
brk>

Best regards
Emanuele Viterbo

-- 
| Emanuele Viterbo         
| Dip. Elettronica  -  Politecnico di Torino  
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