matlab knn算法散点图

Sure! Here's an example code in MATLAB to plot a scatter plot using the k-Nearest Neighbors (k-NN) algorithm:

% Generate some random data points
n = 100; % Number of data points
x = rand(n, 2); % Random x-coordinates
y = rand(n, 1); % Random y-coordinates
labels = randi([1, 3], n, 1); % Random labels (1, 2, or 3)

% Plot the scatter plot
scatter(x(:,1), x(:,2), 25, labels, 'filled');
colormap jet;
colorbar;

% Set labels and title
xlabel('X');
ylabel('Y');
title('Scatter Plot with k-NN Labels');

In this example, we generate random data points with x and y coordinates, as well as random labels. We then use the `scatter` function to create a scatter plot, where the colors of the data points are determined by the labels. The `colormap` and `colorbar` functions are used to create a color legend. Finally, we set the labels and title of the plot using the `xlabel`, `ylabel`, and `title` functions.

You can modify this code to suit your specific needs, such as using your own data or applying the k-NN algorithm to determine the labels.