粗糙集属性约简的代码？
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发布时间：2022-04-20 06:47
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时间：2023-06-24 21:39
% main.m a=[ 1,1,1,1,0,0,0,0,1,1,0,1; 0,0,0,0,0,0,0,0,0,0,0,0; 1,0,1,0,0,0,0,0,0,1,0,0; 0,0,0,1,1,1,1,0,1,0,1,1; 1,0,0,1,1,1,1,1,0,1,1,0; 0,1,0,1,1,1,1,1,1,0,0,1; 1,0,0,0,1,1,1,0,0,1,1,1; 1,1,1,1,0,0,0,0,1,1,0,1; 1,0,1,1,1,0,0,0,1,1,0,1; 1,1,1,1,0,0,0,0,1,1,0,1; 1,0,1,1,1,0,0,0,1,1,0,1; 1,0,1,1,1,0,0,0,1,1,0,1 ]; d=[1;0;0;0;0;0;0;1;1;1;1;1]; pos=posCD(a,d); dismat=dismatrix(a,d,pos); dism=disbe(dismat); core=cor(dism); [red,row]=re(dism); % dismatrix.m % 生成未经处理的区分矩阵dismat function dismat=dismatrix(a,d,pos) [m,n]=size(a); p=1; index1=0;index2=0;index=0; dis=-1*ones(m*(m-1)/2,n); for i=1:m for j=i+1:m if (isxbelongtopos(i,pos)&~isxbelongtopos(j,pos))... |(~isxbelongtopos(i,pos)&isxbelongtopos(j,pos))... |(isxbelongtopos(i,pos)&isxbelongtopos(j,pos)&~isxybelongtoindD(i,j,d)) index2=1; end if index2==0 continue; end for k=1:n if a(i,k)~=a(j,k) dis(p,k)=1; index1=1; else dis(p,k)=0; end end if index1==1 p=p+1;index=1; end index1=0; index2=0; end end if p<=m*(m-1)/2 if index==0 dismat=[]; return; end if dis(p,1)==-1 p=p-1; end else p=m*(m-1)/2; end dismat=dis(1:p,:); % re.m % 对已经处理过的区分矩阵进行知识约简 function [red,row]=re(dism) [m,n]=size(dism); red=[]; row=0; if m<=0 return; end for i=1:n if dism(1,i)~=0 row=row+1; end end red(1:row,:)=zeros(row,n); j=1; for i=1:row while dism(1,j)==0 j=j+1; end red(i,j)=1; j=j+1; end temp=[];tempdis=[]; rowd=0;rowd1=0; for i=2:m j=1; while j<=row temp=uni(dism(i,:),red(j,:)); [s,n]=size(temp); rowd1=rowd+s; tempdis(rowd+1:rowd1,:)=temp; rowd=rowd1; j=j+1; temp=[]; end red=[]; red=disbe(tempdis); tempdis=[]; [row,n]=size(red); rowd=0;rowd1=0; end % disbe.m % 对区分矩阵或者约简矩阵进行化简即去掉包含关系 function dism=disbe(dis) [m,n]=size(dis); p=m; for i=1:m if dis(i,1)~=-1 for j=1:m if i~=j & dis(j,1)~=-1 if dis(i,:)<=dis(j,:) dis(j,1)=-1; p=p-1; elseif dis(i,:)>=dis(j,:) dis(i,:)=dis(j,:); dis(j,1)=-1; p=p-1; end end end end end dism=ones(p,n); j=1; for i=1:p while j<=m & dis(j,1)==-1 j=j+1; end dism(i,:)=dis(j,:); j=j+1; end % posCD.m % a为条件属性矩阵，d为决策属性向量 % pos为正域,保存条件属性矩阵的索引值 function pos=posCD(a,d) [m,n]=size(a); p=m; index=0; for i=1:m if a(i,1)~=-1 for j=i+1:m if a(j,1)~=-1 &(a(i,:)==a(j,:)&d(i)~=d(j)) a(j,1)=-1;p=p-1;index=1; end end if index==1 a(i,1)=-1;p=p-1;index=0; end end end pos=zeros(p,1); i=1; for r=1:p while a(i,1)==-1&i<=m i=i+1; end pos(r)=i; r=r+1; i=i+1; end % cor.m % 对已经处理过的区分矩阵求核 function core=cor(dism) [m,n]=size(dism); core1=zeros(1,n); number=0; for i=1:m num=0;p=0; for j=1:n if dism(i,j)~=0 num=num+1; p=j; end end if num==1 core1(p)=1; number=number+1; end end if number==0 core=0; else core=zeros(1,number); j=1; for i=1:number while core1(j)==0 j=j+1; end core(i)=core1(j); j=j+1; end end % uni.m %对区分矩阵的第i行和red(j,:)运算，即将a中所有的1分别插入到red(j,:)中，待去掉包含关系 function tempred=uni(disa,red) [m,n]=size(red); num=0; for i=1:n if disa(i)~=0 num=num+1; end end tempred=ones(m*num,n); temp=[]; j=1; for i=1:num while disa(j)==0 j=j+1; end temp=red; temp(:,j)=ones(m,1); tempred((i-1)*m+1:i*m,:)=temp; j=j+1; end % isxbelongtopos.m % 判断x是否在正域pos中 % x为索引值 % 返回值p，如果x在pos中p=1否则p=0 function p=isxbelongtopos(x,pos) [m,n]=size(pos); p=0; if x<=0 p=-1; return; end for i=1:m if x==pos(i) p=1; break; end end % isxybelongtoindD.m % 判断x,y是否在indD中 % x,y为索引值 % 返回值p，如果x,y在indD中p=1否则p=0 function p=isxybelongtoindD(x,y,d) if x<=0 | x>size(d) | y<=0 | y>size(d) p=-1; return; end if d(x)==d(y) p=1; else p=0; end
