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#############################################################################
##
#A codemisc.gd GUAVA library Reinald Baart
#A Jasper Cramwinckel
#A Erik Roijackers
#A Eric Minkes
##
## This file contains miscellaneous functions for codes
##
########################################################################
##
#F CodeWeightEnumerator( <code> )
##
## Returns a polynomial over the rationals
## with degree not greater than the length of the code.
## The coefficient of x^i equals
## the number of codewords of weight i.
##
DeclareOperation("CodeWeightEnumerator", [IsCode]);
########################################################################
##
#F CodeDistanceEnumerator( <code>, <word> )
##
## Returns a polynomial over the rationals
## with degree not greater than the length of the code.
## The coefficient of x^i equals
## the number of codewords with distance i to <word>.
DeclareOperation("CodeDistanceEnumerator", [IsCode, IsCodeword]);
########################################################################
##
#F CodeMacWilliamsTransform( <code> )
##
## Returns a polynomial with the weight
## distribution of the dual code as
## coefficients.
##
DeclareOperation("CodeMacWilliamsTransform", [IsCode]);
########################################################################
##
#F WeightVector( <vector> )
##
## Returns the number of non-zeroes in a vector.
DeclareOperation("WeightVector", [IsVector]);
########################################################################
##
#F RandomVector( <len> [, <weight> [, <field> ] ] )
##
DeclareOperation("RandomVector", [IsInt, IsInt, IsField]);
########################################################################
##
#F IsSelfComplementaryCode( <code> )
##
## Return true if <code> is a complementary code, false otherwise.
## A code is called complementary if for every v \in <code>
## also 1 - v \in <code> (where 1 is the all-one word).
##
DeclareProperty("IsSelfComplementaryCode", IsCode);
########################################################################
##
#F IsAffineCode( <code> )
##
## Return true if <code> is affine, i.e. a linear code or
## a coset of a linear code, false otherwise.
##
DeclareProperty("IsAffineCode", IsCode);
########################################################################
##
#F IsAlmostAffineCode( <code> )
##
## Return true if <code> is almost affine, false otherwise.
## A code is called almost affine if the size of any punctured
## code is equal to q^r for some integer r, where q is the
## size of the alphabet of the code.
##
DeclareProperty("IsAlmostAffineCode", IsCode);
########################################################################
##
#F IsGriesmerCode( <code> )
##
## Return true if <code> is a Griesmer code, i.e. if
## n = \sum_{i=0}^{k-1} d/(q^i), false otherwise.
##
DeclareProperty("IsGriesmerCode", IsCode);
########################################################################
##
#F CodeDensity( <code> )
##
## Return the density of <code>, i.e. M*V_q(n,r)/(q^n).
##
DeclareAttribute("CodeDensity", IsCode);
########################################################################
##
#F DecreaseMinimumDistanceUpperBound( <C>, <s>, <iteration> )
##
## Tries to compute the minimum distance of C.
## The algorithm is Leon's, see for more
## information his article.
DeclareOperation("DecreaseMinimumDistanceUpperBound",
[IsCode, IsInt, IsInt]);
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