二元域矩阵求逆MATLAB代码

function [ out ] = inv_bin( in )
%INV_BIN Summary of this function goes here
%   Detailed explanation goes here
%   计算二进制稀疏矩阵的逆
[m,n] = size(in);
if(m~=n)
   fprintf('m~=n\n');
   return ;
end
E = eye(m);
%%
%做行变换，变成下三角阵
for i = 1:m
    noneZerosIndex = find(in(:,i));  %i到end行，第i列非零元
    noneZerosIndex = noneZerosIndex(find(noneZerosIndex>=i));
    if(length(noneZerosIndex)==0)  %该行为0
        randIndex = randi([i+1,m],1);
        %列交换
        temp = in(:,i);
        in(:,i) = in(:,randIndex);
        in(:,randIndex) = temp;
        %E交换
        temp = E(:,i);
        E(:,i) = E(:,randIndex);
        E(:,randIndex) = temp;
    end
    id1 = noneZerosIndex(1);
    %in交换
    temp = in(i,:);
    in(i,:) = in(id1,:);
    in(id1,:) = temp;
    %E交换
    temp = E(i,:);
    E(i,:) = E(id1,:);
    E(id1,:) = temp;
    
    noneZerosIndex = find(in(:,i));  %第i列非零元,用其中的第一行消其他行
    for cc = 1:length(noneZerosIndex)
        if(noneZerosIndex(cc)~=i)  %跳过第i行
            temp = mod(in(noneZerosIndex(cc),:)+in(i,:) , 2);
            in(noneZerosIndex(cc),:) = temp;
            temp = mod(E(noneZerosIndex(cc),:)+E(i,:) , 2);
            E(noneZerosIndex(cc),:) = temp;
        end
    end
end
out = E;
end