Policy Information
ML之SVM:随机产生100个点,建立SVM模型,找出超平面方程
目录
- import numpy as np
- import pylab as pl
- from sklearn import svm
-
- X = np.r_[np.random.randn(100, 2) - [2, 2], np.random.randn(100, 2) + [2, 2]]
-
- Y = [0]*100 +[1]*100
-
- clf = svm.SVC(kernel='linear')
- clf.fit(X, Y)
-
- w = clf.coef_[0]
- a = -w[0]/w[1]
- xx = np.linspace(-5, 5)
- yy = a*xx - (clf.intercept_[0])/w[1]
-
-
- b = clf.support_vectors_[0]
- yy_down = a*xx + (b[1] - a*b[0])
- b = clf.support_vectors_[-1]
- yy_up = a*xx + (b[1] - a*b[0])
-
- print ("w: ", w)
- print ("a: ", a)
-
- print "xx: ", xx
- print "yy: ", yy
- print ("support_vectors_: ", clf.support_vectors_)
- print ("clf.coef_: ", clf.coef_)
-
-
- plot the line, the points, and the nearest vectors to the plane
- pl.plot(xx, yy, 'k-')
- pl.plot(xx, yy_down, 'k--')
- pl.plot(xx, yy_up, 'k--')
-
- pl.scatter(clf.support_vectors_[:, 0], clf.support_vectors_[:, 1],
- s=80, facecolors='none')
- pl.scatter(X[:, 0], X[:, 1], c=Y, cmap=pl.cm.Paired)
-
- pl.axis('tight')
- pl.show()
评论