在MATLAB图例中设置线条颜色？

Question

我正在使用BNT的plotgauss2d函数来可视化当在网络中的其他地方观察到证据时2D高斯节点的响应如何变化.

eng = jtree_inf_engine(bnet);
evidence = cell(1, 2)
eng = enter_evidence(eng, evidence);
marginals = marginal_nodes(eng, 1); p_1 = marginals.T
marginals = marginal_nodes(eng, 2); p_2 = marginals.T
marginals
clf; plotgauss2d(marginals.mu, marginals.Sigma);
hold all;
evidence{1} = 1;
marginals = marginal_nodes(enter_evidence(eng, evidence), 2);
p = plotgauss2d(marginals.mu, marginals.Sigma);
set(p, 'Color', 'green');
evidence{1} = 2;
marginals = marginal_nodes(enter_evidence(eng, evidence), 2);
p = plotgauss2d(marginals.mu, marginals.Sigma);
set(p, 'Color', 'red');
legend({'Unknown', 'Class 1', 'Class 2'});
hold off;

如您所见,图例没有拾取我必须手动设置的更改的绘图颜色.(遗憾的是,plotgauss2d不会像您希望的那样自动循环显示颜色.)

有没有办法设置图例中使用的线条颜色？

Answer 1

所述PLOTGAUSS2D函数返回的分别对应于短轴,长轴,和椭圆3个手柄的载体.所以这里是一个如何存储句柄并在最后调用LEGEND的示例:

figure, hold on
h = zeros(3,3);
h(:,1) = plotgauss2d(rand(2,1), [1 0.5; 0.5 2]);
h(:,2) = plotgauss2d(rand(2,1), [2 -0.5; -0.5 1]);
h(:,3) = plotgauss2d(rand(2,1), [1 0; 0 2]);
hold off
set(h(:,1), 'Color','r')
set(h(:,2), 'Color','g')
set(h(:,3), 'Color','c')
legend(h(1,:), {'1','2','3'})