from numpy import *

def loadDataSet(fileName):

dataMat = []; labelMat = []

fr = open(fileName)

for line in fr.readlines():

lineArr = line.strip().split('\t')

dataMat.append([float(lineArr[0]), float(lineArr[1])])

labelMat.append(float(lineArr[2]))

return dataMat, labelMat

def selectJrand(i, m):

j=i

while (j==i):

j = int(random.uniform(0, m))

return j

def clipAlpha(aj, H, L):

if aj > H:

aj = H

if L > aj:

aj = L

return aj

def smoSimple(dataMatIn, classLabels, C, toler, maxIter):

dataMatrix = mat(dataMatIn); labelMat = mat(classLabels).transpose()

b = 0; m,n = shape(dataMatrix)

alphas = mat(zeros((m,1)))

iter = 0

while (iter < maxIter):

alphaPairsChanged = 0

for i in range(m):

fXi = float(multiply(alphas,labelMat).T*(dataMatrix*dataMatrix[i,:].T)) + b

Ei = fXi - float(labelMat[i])

if ((labelMat[i]*Ei < -toler) and (alphas[i] < C)) or ((labelMat[i]*Ei > toler) and (alphas[i] > 0)):

j = selectJrand(i,m)

fXj = float(multiply(alphas,labelMat).T*(dataMatrix*dataMatrix[j,:].T)) + b

Ej = fXj - float(labelMat[j])

alphaIold = alphas[i].copy(); alphaJold = alphas[j].copy();

if (labelMat[i] != labelMat[j]):

L = max(0, alphas[j] - alphas[i])

H = min(C, C + alphas[j] - alphas[i])

else:

L = max(0, alphas[j] + alphas[i] - C)

H = min(C, alphas[j] + alphas[i])

if L==H: print("L==H"); continue

eta = 2.0 * dataMatrix[i,:]*dataMatrix[j,:].T - dataMatrix[i,:]*dataMatrix[i,:].T - dataMatrix[j,:]*dataMatrix[j,:].T

if eta >= 0: print("eta>=0"); continue

alphas[j] -= labelMat[j]*(Ei - Ej)/eta

alphas[j] = clipAlpha(alphas[j],H,L)

if (abs(alphas[j] - alphaJold) < 0.00001): print("j not moving enough"); continue

alphas[i] += labelMat[j]*labelMat[i]*(alphaJold - alphas[j])

b1 = b - Ei- labelMat[i]*(alphas[i]-alphaIold)*dataMatrix[i,:]*dataMatrix[i,:].T - labelMat[j]*(alphas[j]-alphaJold)*dataMatrix[i,:]*dataMatrix[j,:].T

b2 = b - Ej- labelMat[i]*(alphas[i]-alphaIold)*dataMatrix[i,:]*dataMatrix[j,:].T - labelMat[j]*(alphas[j]-alphaJold)*dataMatrix[j,:]*dataMatrix[j,:].T

if (0 < alphas[i]) and (C > alphas[i]): b = b1

elif (0 < alphas[j]) and (C > alphas[j]): b = b2

else: b = (b1 + b2)/2.0

alphaPairsChanged += 1

print("iter: %d i:%d, pairs changed %d" % (iter,i,alphaPairsChanged))

if (alphaPairsChanged == 0): iter += 1

else: iter = 0

print("iteration number: %d" % iter)

return b, alphas

dataArr, labelArr = loadDataSet('testSet.txt')

b, alphas = smoSimple(dataArr, labelArr, 0.6, 0.001, 40)

print(b)