MATLAB做两类问题Fisher准则的设计与实现

w1 = [-0.4, 0.58, 0.089; ... -0.31, 0.27, -0.04; ... -0.38, 0.055, -0.035; ... -0.15, 0.53, 0.011; ... -0.35, 0.47, 0.034; ... -0.17, 0.69, 0.1; ... -0.011, 0.55, -0.18; ... -0.27, 0.61, 0.12; ... -0.065, 0.49, 0.0012; ... -0.12, 0.054, -0.063]; w2 = [0.8, 1.6, -0.014; ... 1.1, 1.6, 0.48; ... -0.44, -0.41, 0.32; ... 0.047, -0.45, 1.4; ... 0.28, 0.35, 3.1; ... -0.39, -0.48, 0.11; ... 0.34, -0.079, 0.14; ... -0.3, -0.22, 2.2; ... 1.1, 1.2, -0.46; ... 0.18, -0.11, -0.49]; w3 = [1.58, 2.32, -5.8; ... 0.67, 1.58, -4.78; ... 1.04, 1.01, -3.63; ... -1.49, 2.18, -3.39; ... -0.41, 1.21, -4.73; ... 1.39, 3.61, 2.87; ... 1.2, 1.4, -1.89; ... -0.92, 1.44, -3.22; ... 0.45, 1.33, -4.38; ... -0.76, 0.84, -1.96]; xx1 = [-0.7, 0.58, 0.089]'; xx2 = [0.047, -0.4, 1.04]'; s1 = cov(w2, 1); ml = mean(w2)'; s2 = cov(w3, 1); m2 = mean(w3)'; sw = s1 + s2; w = inv(sw) * (ml - m2); y0 = (w' * ml + w' * m2) / 2; figure(1); for i = 1:1:10 plot3(w2(i, 1), w2(i, 2), w2(i, 3), 'r*'); hold on; plot3(w3(i, 1), w3(i, 2), w3(i, 3), 'bo'); end; z1 = w' * w2'; z2 = w' * w3'; figure(2) xmin = min(min(w2(:, 1)), min(w3(:, 1))); xmax = max(max(w2(:, 1)), max(w3(:, 1))); x = xmin - 1:(xmax - xmin) / 100:xmax; plot3(30*x, 30*x*w(2, :)/w(1, :), 30*x*w(3, :)/w(1, :), 'k'); hold on; for i = 1:10 plot3(z1(i)*w(1), z1(i)*w(2), z1(i)*w(3), 'rx') hold on plot3(z2(i)*w(1), z2(i)*w(2), z2(i)*w(3), 'bp') end hold off yl = w' * xx1; if yl > y0 fprintf('测试数据xx1属于w2类\n'); else fprintf('测试数据xx1属于w3类\n'); end y2 = w' * xx2; if y2 > y0 fprintf('测试数据xx2属于w2类\n'); else fprintf('测试数据xx2属于w3类\n'); end