1、運(yùn)行環(huán)境：eclipse+pydev+Anaconda2-4.4.0(python2.7)，含numpy、matplotlib(制圖)。

2、代碼：

# -*- coding: utf-8 -*- __author__ = 'Jason.F'from numpy import * import matplotlib.pyplot as plt import operator import time#導(dǎo)入數(shù)據(jù)，格式： value1 value2 label #3.542485 1.977398 -1 #3.018896 2.556416 1 def loadDataSet(fileName):dataMat = []labelMat = []with open(fileName) as fr:for line in fr.readlines():lineArr = line.strip().split()labelMat.append(float(lineArr[2]))#i=lineArr.__len__()#for i in range(1,i):dataMat.append([float(lineArr[0]),float(lineArr[1])]) return dataMat, labelMatdef selectJrand(i, m):j = iwhile (j == i):j = int(random.uniform(0, m))return jdef clipAlpha(aj, H, L):if aj > H:aj = Hif L > aj:aj = Lreturn ajclass optStruct:def __init__(self, dataMatIn, classLabels, C, toler):self.X = dataMatInself.labelMat = classLabelsself.C = Cself.tol = tolerself.m = shape(dataMatIn)[0]self.alphas = mat(zeros((self.m, 1)))self.b = 0self.eCache = mat(zeros((self.m, 2)))def calcEk(oS, k):fXk = float(multiply(oS.alphas, oS.labelMat).T * (oS.X * oS.X[k, :].T)) + oS.bEk = fXk - float(oS.labelMat[k])return Ekdef selectJ(i, oS, Ei):maxK = -1maxDeltaE = 0Ej = 0oS.eCache[i] = [1, Ei]validEcacheList = nonzero(oS.eCache[:, 0].A)[0]if (len(validEcacheList)) > 1:for k in validEcacheList:if k == i:continueEk = calcEk(oS, k)deltaE = abs(Ei - Ek)if (deltaE > maxDeltaE):maxK = kmaxDeltaE = deltaEEj = Ekreturn maxK, Ejelse:j = selectJrand(i, oS.m)Ej = calcEk(oS, j)return j, Ejdef updateEk(oS, k):Ek = calcEk(oS, k)oS.eCache[k] = [1, Ek]def innerL(i, oS):Ei = calcEk(oS, i)if ((oS.labelMat[i] * Ei < -oS.tol) and (oS.alphas[i] < oS.C)) or ((oS.labelMat[i] * Ei > oS.tol) and (oS.alphas[i] > 0)):j, Ej = selectJ(i, oS, Ei)alphaIold = oS.alphas[i].copy()alphaJold = oS.alphas[j].copy()if (oS.labelMat[i] != oS.labelMat[j]):L = max(0, oS.alphas[j] - oS.alphas[i])H = min(oS.C, oS.C + oS.alphas[j] - oS.alphas[i])else:L = max(0, oS.alphas[j] + oS.alphas[i] - oS.C)H = min(oS.C, oS.alphas[j] + oS.alphas[i])if (L == H):# print("L == H")return 0eta = 2.0 * oS.X[i, :] * oS.X[j, :].T - oS.X[i, :] * oS.X[i, :].T - oS.X[j, :] * oS.X[j, :].Tif eta >= 0:# print("eta >= 0")return 0oS.alphas[j] -= oS.labelMat[j] * (Ei - Ej) / etaoS.alphas[j] = clipAlpha(oS.alphas[j], H, L)updateEk(oS, j)if (abs(oS.alphas[j] - alphaJold) < 0.00001):# print("j not moving enough")return 0oS.alphas[i] += oS.labelMat[j] * oS.labelMat[i] * (alphaJold - oS.alphas[j])updateEk(oS, i)b1 = oS.b - Ei - oS.labelMat[i] * (oS.alphas[i] - alphaIold) * oS.X[i, :] * oS.X[i, :].T - oS.labelMat[j] * (oS.alphas[j] - alphaJold) * oS.X[i, :] * oS.X[j, :].Tb2 = oS.b - Ei - oS.labelMat[i] * (oS.alphas[i] - alphaIold) * oS.X[i, :] * oS.X[j, :].T - oS.labelMat[j] * (oS.alphas[j] - alphaJold) * oS.X[j, :] * oS.X[j, :].Tif (0 < oS.alphas[i]) and (oS.C > oS.alphas[i]):oS.b = b1elif (0 < oS.alphas[j]) and (oS.C > oS.alphas[j]):oS.b = b2else:oS.b = (b1 + b2) / 2.0return 1else:return 0def smoP(dataMatIn, classLabels, C, toler, maxIter, kTup=('lin', 0)):"""輸入：數(shù)據(jù)集, 類別標(biāo)簽, 常數(shù)C, 容錯(cuò)率, 最大循環(huán)次數(shù)輸出：目標(biāo)b, 參數(shù)alphas"""oS = optStruct(mat(dataMatIn), mat(classLabels).transpose(), C, toler)iterr = 0entireSet = TruealphaPairsChanged = 0while (iterr < maxIter) and ((alphaPairsChanged > 0) or (entireSet)):alphaPairsChanged = 0if entireSet:for i in range(oS.m):alphaPairsChanged += innerL(i, oS)# print("fullSet, iter: %d i:%d, pairs changed %d" % (iterr, i, alphaPairsChanged))iterr += 1else:nonBoundIs = nonzero((oS.alphas.A > 0) * (oS.alphas.A < C))[0]for i in nonBoundIs:alphaPairsChanged += innerL(i, oS)#內(nèi)積# print("non-bound, iter: %d i:%d, pairs changed %d" % (iterr, i, alphaPairsChanged))iterr += 1if entireSet:entireSet = Falseelif (alphaPairsChanged == 0):entireSet = True# print("iteration number: %d" % iterr)return oS.b, oS.alphasdef calcWs(alphas, dataArr, classLabels):"""輸入：alphas, 數(shù)據(jù)集, 類別標(biāo)簽輸出：目標(biāo)w"""X = mat(dataArr)labelMat = mat(classLabels).transpose()m, n = shape(X)w = zeros((n, 1))for i in range(m):w += multiply(alphas[i] * labelMat[i], X[i, :].T)return wdef plotFeature(dataMat, labelMat, weights, b):dataArr = array(dataMat)n = shape(dataArr)[0]xcord1 = []; ycord1 = []xcord2 = []; ycord2 = []for i in range(n):if int(labelMat[i]) == 1:xcord1.append(dataArr[i, 0])ycord1.append(dataArr[i, 1])else:xcord2.append(dataArr[i, 0])ycord2.append(dataArr[i, 1])fig = plt.figure()ax = fig.add_subplot(111)ax.scatter(xcord1, ycord1, s=30, c='red', marker='s')ax.scatter(xcord2, ycord2, s=30, c='green')x = arange(2, 7.0, 0.1)y = (-b[0, 0] * x) - 10 / linalg.norm(weights)ax.plot(x, y)plt.xlabel('X1'); plt.ylabel('X2')plt.show()def main():trainDataSet, trainLabel = loadDataSet('D:\set.txt')b, alphas = smoP(trainDataSet, trainLabel, 0.6, 0.0001, 40)ws = calcWs(alphas, trainDataSet, trainLabel)print("ws = \n", ws)print("b = \n", b)plotFeature(trainDataSet, trainLabel, ws, b)if __name__ == '__main__':start = time.clock()main()end = time.clock()print('finish all in %s' % str(end - start))
3、set.txt樣例數(shù)據(jù)

3.542485 1.977398 -1 3.018896 2.556416 -1 7.551510 -1.580030 1 2.114999 -0.004466 -1 8.127113 1.274372 1 7.108772 -0.986906 1 8.610639 2.046708 1 2.326297 0.265213 -1 3.634009 1.730537 -1 0.341367 -0.894998 -1 3.125951 0.293251 -1 2.123252 -0.783563 -1 0.887835 -2.797792 -1 7.139979 -2.329896 1 1.696414 -1.212496 -1 8.117032 0.623493 1 8.497162 -0.266649 1 4.658191 3.507396 -1 8.197181 1.545132 1 1.208047 0.213100 -1 1.928486 -0.321870 -1 2.175808 -0.014527 -1 7.886608 0.461755 1 3.223038 -0.552392 -1 3.628502 2.190585 -1 7.407860 -0.121961 1 7.286357 0.251077 1 2.301095 -0.533988 -1 -0.232542 -0.547690 -1 3.457096 -0.082216 -1 3.023938 -0.057392 -1 8.015003 0.885325 1 8.991748 0.923154 1 7.916831 -1.781735 1 7.616862 -0.217958 1 2.450939 0.744967 -1 7.270337 -2.507834 1 1.749721 -0.961902 -1 1.803111 -0.176349 -1 8.804461 3.044301 1 1.231257 -0.568573 -1 2.074915 1.410550 -1 -0.743036 -1.736103 -1 3.536555 3.964960 -1 8.410143 0.025606 1 7.382988 -0.478764 1 6.960661 -0.245353 1 8.234460 0.701868 1 8.168618 -0.903835 1 1.534187 -0.622492 -1 9.229518 2.066088 1 7.886242 0.191813 1 2.893743 -1.643468 -1 1.870457 -1.040420 -1 5.286862 -2.358286 1 6.080573 0.418886 1 2.544314 1.714165 -1 6.016004 -3.753712 1 0.926310 -0.564359 -1 0.870296 -0.109952 -1 2.369345 1.375695 -1 1.363782 -0.254082 -1 7.279460 -0.189572 1 1.896005 0.515080 -1 8.102154 -0.603875 1 2.529893 0.662657 -1 1.963874 -0.365233 -1 8.132048 0.785914 1 8.245938 0.372366 1 6.543888 0.433164 1 -0.236713 -5.766721 -1 8.112593 0.295839 1 9.803425 1.495167 1 1.497407 -0.552916 -1 1.336267 -1.632889 -1 9.205805 -0.586480 1 1.966279 -1.840439 -1 8.398012 1.584918 1 7.239953 -1.764292 1 7.556201 0.241185 1 9.015509 0.345019 1 8.266085 -0.230977 1 8.545620 2.788799 1 9.295969 1.346332 1 2.404234 0.570278 -1 2.037772 0.021919 -1 1.727631 -0.453143 -1 1.979395 -0.050773 -1 8.092288 -1.372433 1 1.667645 0.239204 -1 9.854303 1.365116 1 7.921057 -1.327587 1 8.500757 1.492372 1 1.339746 -0.291183 -1 3.107511 0.758367 -1 2.609525 0.902979 -1 3.263585 1.367898 -1 2.912122 -0.202359 -1 1.731786 0.589096 -1 2.387003 1.573131 -1
4、執(zhí)行結(jié)果：

('ws = \n', array([[ 0.65307162],[-0.17196128]])) ('b = \n', matrix([[-2.89901748]])) finish all in 19.5581056613

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