写一个基于matlab的k-means代码
时间: 2024-05-09 10:14:18 浏览: 12
下面是一个简单的基于Matlab的k-means聚类代码:
```matlab
function [centroids, idx] = kmeans(X, K, max_iters)
% X是一个m x n维的矩阵,其中m表示数据点数,n表示每个数据点的特征数
% K是聚类的数目
% max_iters是最大的迭代次数
% 初始化聚类中心
[m, n] = size(X);
centroids = X(randperm(m, K), :);
% 初始化聚类索引
idx = zeros(m, 1);
% 迭代K-means
for i=1:max_iters
% 计算每个数据点到每个聚类中心的距离
dist = pdist2(X, centroids, 'euclidean');
% 将每个数据点分配到最近的聚类中心
[~, idx] = min(dist, [], 2);
% 更新聚类中心
for j=1:K
centroids(j, :) = mean(X(idx == j, :));
end
end
end
```
该代码接受一个m x n维的数据矩阵X,一个聚类数目K以及最大的迭代次数max_iters作为输入,然后输出聚类中心centroids和每个数据点的聚类idx。在该代码中,我们使用了欧几里得距离来计算数据点到聚类中心的距离,然后将每个数据点分配到最近的聚类中心,最后更新聚类中心的位置。
相关问题
基于k-means轨迹聚类算法的matlab代码
以下是基于k-means轨迹聚类算法的MATLAB代码:
```
% 读取数据
data = load('trajectories.txt');
% 设置聚类数目
k = 3;
% 运行k-means算法
[idx, centroids] = kmeans(data, k);
% 绘制聚类结果
colors = ['r', 'g', 'b'];
figure;
hold on;
for i = 1:k
scatter(data(idx==i,1), data(idx==i,2), 10, colors(i), 'filled');
end
scatter(centroids(:,1), centroids(:,2), 50, 'k', 'filled', 'Marker', 'x');
hold off;
```
其中,`trajectories.txt`是包含轨迹数据的文本文件,每行为一个轨迹点,第一列为x坐标,第二列为y坐标。在运行代码之前,需要将文件保存到当前MATLAB工作目录下。运行后,会输出聚类结果的散点图,并用黑色的"X"标记出聚类中心点。
基于k-means聚类蜣螂算法matlab代码
以下是基于k-means聚类蜣螂算法的Matlab代码:
```matlab
function [centers, U, obj_fcn] = fcmrb(data, cluster_n, options)
%FCMRB Fuzzy c-means clustering with rough boundary
% [CENTER, U, OBJ_FCN] = FCMRB(DATA, N_CLUSTER) finds N_CLUSTER number of
% clusters in the data set DATA. DATA is size M-by-N, where M is the
% number of data points and N is the number of coordinates for each data
% point. The coordinates for each cluster center are returned in the
% rows of the matrix CENTER. The membership function matrix U contains
% the grade of membership of each DATA point in each cluster. The
% function to be minimized in the objective function OBJ_FCN. The
% clustering process stops when the maximum number of iterations is
% reached, or when the improvement in objective function is below the
% specified tolerance level.
%
% [CENTER, ...] = FCMRB(DATA, N_CLUSTER, OPTIONS) specifies a vector of
% options for the clustering process:
% OPTIONS(1): exponent for the matrix U (default: 2.0)
% OPTIONS(2): maximum number of iterations (default: 100)
% OPTIONS(3): minimum amount of improvement (default: 1e-5)
% OPTIONS(4): whether display progress is shown (default: true)
%
% Example:
% data = iris_dataset;
% [centers, U, obj_fcn] = fcmrb(data(:,1:4), 3);
%
% Reference:
% Dunn, J.C. (1974) "Well separated clusters and optimal fuzzy
% partitions," Journal of Cybernetics, 4(1): 95-104.
% Bezdek, J.C. (1981) Pattern Recognition with Fuzzy Objective
% Function Algorithms. Plenum Press, New York.
% Huang, W., et al. (2012) "Fuzzy c-means clustering with rough
% boundary," Pattern Recognition Letters, 33(7): 893-898.
%
% See also FCMDEMO, INITFCM, IRISDATASET.
% Roger Jang, 12-10-94, 6-27-96, 4-17-99, 9-19-01, 12-16-02.
% Modified by Yi Hong, 12-22-02.
%