MATLAB爱好者论坛-LabFans.com

MATLAB爱好者论坛-LabFans.com (https://www.labfans.com/bbs/index.php)
-   资料存档 (https://www.labfans.com/bbs/forumdisplay.php?f=72)
-   -   在MATLAB中的Kmeans聚类中获取最接近数据点的索引到中心点 (https://www.labfans.com/bbs/showthread.php?t=24208)

poster 2019-12-10 20:48

在MATLAB中的Kmeans聚类中获取最接近数据点的索引到中心点
 
我正在使用MATLAB中的K-means进行聚类。如您所知,用法如下:

[IDX,C] = kmeans(X,k) 其中IDX给出了X中每个数据点的簇号,C给出了每个簇的质心。我需要获取最接近该质点的索引(实际数据集X中的行号)。有谁知道我该怎么做?谢谢



[B]回答:[/B]

[URL="https://stackoverflow.com/questions/4400070/getting-the-index-of-closest-data-point-to-the-centriods-in-kmeans-clustering-in/4400125#4400125"]@Dima[/URL]提到的“暴力方法”如下

%# loop through all clusters for iCluster = 1:max(IDX) %# find the points that are part of the current cluster currentPointIdx = find(IDX==iCluster); %# find the index (among points in the cluster) %# of the point that has the smallest Euclidean distance from the centroid %# bsxfun subtracts coordinates, then you sum the squares of %# the distance vectors, then you take the minimum [~,minIdx] = min(sum(bsxfun(@minus,X(currentPointIdx,:),C(iCluster,:)).^2,2)); %# store the index into X (among all the points) closestIdx(iCluster) = currentPointIdx(minIdx); end 要获取最接近聚类中心k的点的坐标,请使用

X(closestIdx(k),:)

[url=https://stackoverflow.com/questions/4400070]更多&回答...[/url]


所有时间均为北京时间。现在的时间是 01:12

Powered by vBulletin
版权所有 ©2000 - 2025,Jelsoft Enterprises Ltd.