from math import sqrt def multipl(a,b): sumofab=0.0 for i in range(len(a)): temp=a[i]*b[i] sumofab+=temp return sumofab def corrcoef(x,y): n=len(x) #求和 sum1=sum(x) sum2=sum(y) #求乘积之和 sumofxy=multipl(x,y) #求平方和 sumofx2 = sum([pow(i,2) for i in x]) sumofy2 = sum([pow(j,2) for j in y]) num=sumofxy-(float(sum1)*float(sum2)/n) #计算皮尔逊相关系数 den=sqrt((sumofx2-float(sum1**2)/n)*(sumofy2-float(sum2**2)/n)) return num/den x = [0,1,0,3] y = [0,1,1,1] print corrcoef(x,y) #0.471404520791