project1.py 文件源码

def plot3DPrincipalComponents(X,y,classNames,prin1,prin2,prin3,attributeNames):
    C = len(classNames)    
    Y = X - np.ones((len(X),1))*X.mean(0)

    U,S,V = linalg.svd(Y,full_matrices=False)
    V = mat(V).T

    Z = Y * V

    f = figure()
    hold(True)
    colors = ['blue', 'green']
    ax = f.add_subplot(111, projection='3d')
    for c in range(C):
        class_mask = (y==c).A.ravel()
        ax.scatter(Z[class_mask,prin1].A, Z[class_mask,prin2].A, Z[class_mask,prin3].A, c=colors[c])    
    ax.set_xlabel('PC{0}'.format(prin1+1))
    ax.set_ylabel('PC{0}'.format(prin2+1))
    ax.set_zlabel('PC{0}'.format(prin3+1))
    title("3D plot of principal components")
    legend(attributeNames)


#Using CHD as attribute