cal_obj.py 文件源码

def cal_obj(v,w1,alpha,w2,events,trainT): #function [obj]=cal_obj(v,w1,alpha,w2,events,trainT)
    T=trainT
    N=len(events)
    s=events
    old_sum2 = 0
    obj = numpy.log(v*numpy.exp(-w1*s[0])) #log(v*exp(-w1*s(1)));
    for i in range(1,N): #i=2:N
        mu = v*numpy.exp(-w1*s[i]) #v*exp(-w1*s(i));
        sum1 = mu
        sum2 = (old_sum2 + alpha)*numpy.exp(-w2*(s[i]-s[i-1])) #(old_sum2+ alpha)*exp(-w2*(s(i)-s(i-1)));
        old_sum2 = sum2
        obj=obj+numpy.log(sum1+sum2)
    #end
    ____1 = numpy.exp(-w2*(T-numpy.mat(s)))
    ____2 = numpy.sum((1-    ____1))*alpha/float(w2)
    obj= obj - ____2 #obj - sum((1-exp(-w2*(T-s))))*alpha/w2;
    obj = obj - (v/w1) * (1 - numpy.exp(-w1*T)) #obj - v/w1*(1-exp(-w1*T));
    return obj
#end