é¦å
ç»åºåå§æ°æ®{x1,x2,...,xn}ï¼è¿äºæ°æ®æ²¡æ被æ è®°çã
åå§åk个éæºæ°æ®u1,u2,...,ukãè¿äºxnåuké½æ¯åéã
æ ¹æ®ä¸é¢ä¸¤ä¸ªå
¬å¼è¿ä»£å°±è½æ±åºæç»ææçu,è¿äºuå°±æ¯æç»ææç±»çä¸å¿ä½ç½®ã
å
¬å¼ä¸ï¼
ææå°±æ¯æ±åºæææ°æ®ååå§åçéæºæ°æ®çè·ç¦»ï¼ç¶åæ¾åºè·ç¦»æ¯ä¸ªåå§æ°æ®æè¿çæ°æ®ã
å
¬å¼äºï¼
ææå°±æ¯æ±åºææåè¿ä¸ªåå§æ°æ®æè¿åå§æ°æ®çè·ç¦»çåå¼ã
ç¶åä¸æè¿ä»£ä¸¤ä¸ªå
¬å¼ï¼ç´å°ææçué½ä¸æä¹ååäºï¼å°±ç®å®æäºã
å
ççä¸äºç»æï¼
ç¨ä¸ä¸ªäºç»´é«æ¯åå¸æ°æ®ç»åºçå¾ï¼
éè¿å¯¹æ²¡ææ è®°çåå§æ°æ®è¿è¡kmeansèç±»å¾å°çåç±»ï¼ååæ¯æç»è¿ä»£ä½ç½®ï¼
ä¸é¢æ¯Matlab代ç ï¼è¿éæææµè¯æ°æ®æ¹ä¸ºäºä¸ç»´äºï¼å½æ°æ¯å¯ä»¥å¤çåç§ç»´åº¦çã
main.m
clear all;
close all;
clc;
%第ä¸ç±»æ°æ®
mu1=[0 0 0]; %åå¼
S1=[0.3 0 0;0 0.35 0;0 0 0.3]; %åæ¹å·®
data1=mvnrnd(mu1,S1,100); %产çé«æ¯åå¸æ°æ®
%%第äºç±»æ°æ®
mu2=[1.25 1.25 1.25];
S2=[0.3 0 0;0 0.35 0;0 0 0.3];
data2=mvnrnd(mu2,S2,100);
%第ä¸ä¸ªç±»æ°æ®
mu3=[-1.25 1.25 -1.25];
S3=[0.3 0 0;0 0.35 0;0 0 0.3];
data3=mvnrnd(mu3,S3,100);
%æ¾ç¤ºæ°æ®
plot3(data1(:,1),data1(:,2),data1(:,3),'+');
hold on;
plot3(data2(:,1),data2(:,2),data2(:,3),'r+');
plot3(data3(:,1),data3(:,2),data3(:,3),'g+');
grid on;
%ä¸ç±»æ°æ®åæä¸ä¸ªä¸å¸¦æ å·çæ°æ®ç±»
data=[data1;data2;data3]; %è¿éçdataæ¯ä¸å¸¦æ å·ç
%k-meansèç±»
[u re]=KMeans(data,3); %æå产ç带æ å·çæ°æ®ï¼æ å·å¨æææ°æ®çæåï¼ææå°±æ¯æ°æ®åå ä¸ç»´åº¦
[m n]=size(re);
%æåæ¾ç¤ºèç±»åçæ°æ®
figure;
hold on;
for i=1:m
if re(i,4)==1
plot3(re(i,1),re(i,2),re(i,3),'ro');
elseif re(i,4)==2
plot3(re(i,1),re(i,2),re(i,3),'go');
else
plot3(re(i,1),re(i,2),re(i,3),'bo');
end
end
grid on;
KMeans.m
%Næ¯æ°æ®ä¸å
±åå¤å°ç±»
%dataæ¯è¾å
¥çä¸å¸¦åç±»æ å·çæ°æ®
%uæ¯æ¯ä¸ç±»çä¸å¿
%reæ¯è¿åç带åç±»æ å·çæ°æ®
function [u re]=KMeans(data,N)
[m n]=size(data); %mæ¯æ°æ®ä¸ªæ°ï¼næ¯æ°æ®ç»´æ°
ma=zeros(n); %æ¯ä¸ç»´æ大çæ°
mi=zeros(n); %æ¯ä¸ç»´æå°çæ°
u=zeros(N,n); %éæºåå§åï¼æç»è¿ä»£å°æ¯ä¸ç±»çä¸å¿ä½ç½®
for i=1:n
ma(i)=max(data(:,i)); %æ¯ä¸ç»´æ大çæ°
mi(i)=min(data(:,i)); %æ¯ä¸ç»´æå°çæ°
for j=1:N
u(j,i)=ma(i)+(mi(i)-ma(i))*rand(); %éæºåå§åï¼ä¸è¿è¿æ¯å¨æ¯ä¸ç»´[min max]ä¸åå§å好äº
end
end
while 1
pre_u=u; %ä¸ä¸æ¬¡æ±å¾çä¸å¿ä½ç½®
for i=1:N
tmp{i}=[]; % å
¬å¼ä¸ä¸çx(i)-uj,为å
¬å¼ä¸å®ç°ååå¤
for j=1:m
tmp{i}=[tmp{i};data(j,:)-u(i,:)];
end
end
quan=zeros(m,N);
for i=1:m %å
¬å¼ä¸çå®ç°
c=[];
for j=1:N
c=[c norm(tmp{j}(i,:))];
end
[junk index]=min(c);
quan(i,index)=norm(tmp{index}(i,:));
end
for i=1:N %å
¬å¼äºçå®ç°
for j=1:n
u(i,j)=sum(quan(:,i).*data(:,j))/sum(quan(:,i));
end
end
if norm(pre_u-u)<0.1 %ä¸æè¿ä»£ç´å°ä½ç½®ä¸ååå
break;
end
end
re=[];
for i=1:m
tmp=[];
for j=1:N
tmp=[tmp norm(data(i,:)-u(j,:))];
end
[junk index]=min(tmp);
re=[re;data(i,:) index];
end
end
温馨提示:答案为网友推荐,仅供参考