detreeexp1_2.asv

支持向量机工具箱

%设置全局变量 meas species bad numobs
global meas species bad numobs quadclass

%散点图
gscatter(meas(:,1), meas(:,2), species,'mgb','vsp');
xlabel('Sepal 长度');
ylabel('Sepal 宽度');

%二次分类
quadclass= classify(meas(:,1:2),meas(:,1:2),species);

%计算错误分类      strcmp函数比较字符串
bad = ~strcmp(quadclass,species);
%计算meas第一列大小
numobs = size(meas,1);
%sum函数求元素的和
sum(bad) / numobs;

%在散点图上显示错误分类 用x表示
hold on;
plot(meas(bad,1), meas(bad,2), 'kx');
hold off;