IntersectionCode( C_1, C_2 )
IntersectionCode
returns the intersection of codes C_1 and C_2.
This code consists of all codewords that are both in C_1 and C_2.
If both codes are linear, the result is also linear. If both are cyclic,
the result is also cyclic.
gap> C := CyclicCodes(7, GF(2)); [ a cyclic [7,7,1]0 enumerated code over GF(2), a cyclic [7,6,1..2]1 enumerated code over GF(2), a cyclic [7,3,1..4]2..3 enumerated code over GF(2), a cyclic [7,0,7]7 enumerated code over GF(2), a cyclic [7,3,1..4]2..3 enumerated code over GF(2), a cyclic [7,4,1..3]1 enumerated code over GF(2), a cyclic [7,1,7]3 enumerated code over GF(2), a cyclic [7,4,1..3]1 enumerated code over GF(2) ] gap> IntersectionCode(C[6], C[8]) = C[7]; true
GAP 3.4.4