? 求该债券的到期收益率 fun5<-function(extra,m,t,pv){ r<-m/extra sum<-0
for(i in 0:(t-1)){
a<-200/((1+r/2)^i) sum<-sum+a }
sum<-sum+extra rf<-sum/pv-1 return (rf) }
> fun5<-function(extra,m,t,pv){ + r<-m/extra + sum<-0
+ for(i in 0:(t-1)){
+ a<-200/((1+r/2)^i) + sum<-sum+a + }
+ sum<-sum+extra + rf<-sum/pv-1 + return (rf) + }
>fun5(2500,200,40,2364) [1] 1.799026