屬性約簡(jiǎn)MATLAB算法有實(shí)例有講解

1、粗糙集 屬性約簡(jiǎn)題目:  SARS 診斷注：這是我學(xué)粗糙集時(shí)老師給的作業(yè) U干咳呼吸困難 血液檢測(cè)高燒38度 X射線濃痰血細(xì)胞多寒戰(zhàn)肌肉酸痛乏力胸膜痛頭痛非典111 1100001101120 0 00000000000310 1000000100040 0 0111101011051 0 01111101100601 01111110010710 00111001110811 11000011011910 111000110

2、11101 1 11000011011111 0 11100011011121 0 11100011011屬性約簡(jiǎn)的順序如下：求正域、生成未經(jīng)處理的區(qū)分矩陣、對(duì)區(qū)分矩陣進(jìn)行化簡(jiǎn)、求核、對(duì)已經(jīng)處理過(guò)的區(qū)分矩陣進(jìn)行屬性約簡(jiǎn)。約簡(jiǎn)后的決策表有26行,所有12個(gè)屬性都是正域中的屬性，核為空 程序:% main.mtic;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

3、,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,

4、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=redu(dism);time=toc% dismatrix.m% 生成未經(jīng)處理的區(qū)分矩陣dismatfunction dismat=dismatrix(a,d,pos)m,n=size(a);p

5、=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,po

6、s)&isxbelongtopos(j,pos).                |(isxbelongtopos(i,pos)&isxbelongtopos(j,pos)&isxybelongtoindD(i,j,d)            index2=1;    

7、60;   end        if index2=0            continue;        end        for k=1:n         

8、;   if a(i,k)=a(j,k)                dis(p,k)=1;                index1=1;            e

9、lse dis(p,k)=0;            end        end        if index1=1            p=p+1;index=1;     

10、0;  end        index1=0;        index2=0;    endendif p<=m*(m-1)/2     if index=0        dismat=;        return; 

11、;   end    if dis(p,1)=-1        p=p-1;    endelse p=m*(m-1)/2;enddismat=dis(1:p,:);% redu.m% 對(duì)已經(jīng)處理過(guò)的區(qū)分矩陣進(jìn)行知識(shí)約簡(jiǎn)function red,row=redu(dism)m,n=size(dism);red=;row=0;if m<=0    return;endfor i=1:n  &

12、#160; if dism(1,i)=0        row=row+1;    endendred(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

13、;endtemp=;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;  

14、60;     tempdis(rowd+1:rowd1,:)=temp;        rowd=rowd1;        j=j+1;        temp=;    end    red=;    red=disbe(tempdis); &

15、#160;  tempdis=;    row,n=size(red);     rowd=0;rowd1=0;end % disbe.m% 對(duì)區(qū)分矩陣或者約簡(jiǎn)矩陣進(jìn)行化簡(jiǎn)即去掉包含關(guān)系function dism=disbe(dis)m,n=size(dis);p=m;for i=1:m    if dis(i,1)=-1        for j=1:m    &#

16、160;        if i=j & dis(j,1)=-1                 if dis(i,:)<=dis(j,:)                  

17、   dis(j,1)=-1;                     p=p-1;                 elseif dis(i,:)>=dis(j,:)    

18、;                 dis(i,:)=dis(j,:);                     dis(j,1)=-1;        

19、60;            p=p-1;                 end             end        

20、               end    endenddism=ones(p,n);j=1;for i=1:p    while j<=m & dis(j,1)=-1        j=j+1;    end    dism(i,:)=dis(j,:);

21、    j=j+1;end % posCD.m% a為條件屬性矩陣，d為決策屬性向量% pos為正域,保存條件屬性矩陣的索引值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)

22、=-1 &(a(i,:)=a(j,:)&d(i)=d(j)                a(j,1)=-1;p=p-1;index=1;            end        end     &#

23、160;  if index=1            a(i,1)=-1;p=p-1;index=0;        end    endendpos=zeros(p,1);i=1;for r=1:p    while a(i,1)=-1&i<=m       

24、i=i+1;    end    pos(r)=i;    r=r+1;    i=i+1;end % cor.m% 對(duì)已經(jīng)處理過(guò)的區(qū)分矩陣求核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     

25、60;  if dism(i,j)=0            num=num+1;            p=j;        end    end    if num=1     

26、60;  core1(p)=1;        number=number+1;    endendif number=0    core=0;else    core=zeros(1,number);    j=1;    for i=1:number        while core1(j)=

27、0            j=j+1;        end        core(i)=core1(j);        j=j+1;    endend % uni.m%對(duì)區(qū)分矩陣的第i行和red(j,:)運(yùn)算，即將a中%所有的1分別插入到red(j,:)中，待去掉包含關(guān)系function tempred=uni(disa,red)m,n=size(red);num=0;for i=1:n    if disa(i)=0        num=num+1;