1
我在MATLAB如下:在Matlab中使用princomp()?
>> X = [ 123 982 123 ; 434 233 842; 143 239 583; 733 292 503]
X =
123 982 123
434 233 842
143 239 583
733 292 503
[coeff,score] = princomp(X)
coeff =
-0.3714 0.9202 0.1241
0.7330 0.2085 0.6475
-0.5700 -0.3314 0.7519
score =
709.3366 26.4384 30.9912
-364.9469 -81.8490 125.1814
-104.8637 -262.5228 -101.7805
-239.5260 317.9334 -54.3921
>> X * coeff
ans =
603.9913 277.1477 743.6166
-470.2922 168.8604 837.8069
-210.2090 -11.8134 610.8450
-344.8714 568.6428 658.2333
爲什麼沒有得分= X * _係數?
我相信X * coeff與沿着主分量軸投影原始數據相同。
我相信這是因爲該係數不正交。查看http://www.mathworks.com/help/stats/feature-transformation.html#f75476獲取更多信息 – Esteban
那麼我應該在計算投影之前理想地使它們正交嗎? – Sykalen