cc4.m

ldpc码中

function c4=cc4(H)
%c4=cc4(H)
%如果包含有4环，则c4=1，否则c4=0

dim=size(H);
cols=dim(2);

h1idx=zeros(6, cols);

%计算列重
for j=1:cols
   ind=find(H(:,j)==1);
   h1idx(1,j)=length(ind);
   h1idx(2:h1idx(1,j)+1,j)=ind;
end

c4=checkcycle4(h1idx);