请教各位专家，我在用一组数据，一共两列，一列为日期，一列为发病数，计算R0，下面是我输入的算法，请问哪里有问题呢？
setwd("D:/")
> data<-read.csv('DL33.csv')(两列数据,一列为日期data,一列为病例数)
> data$date<-as.Date(data$date)
> library(R0)
Loading required package: MASS
Warning message:
package ‘R0’ was built under R version 3.5.3 (我用的是R version 3.5.1)
> install.packages("MASS")
  There is a binary version available but the source version is
  later:
       binary   source needs_compilation
MASS 7.3-51.5 7.3-51.6              TRUE

  Binaries will be installed
Warning: package ‘MASS’ is in use and will not be installed(这个的意思是不需要再安装了吧)
> install.packages("R0")
Warning: package ‘R0’ is in use and will not be installed(这个的意思是不需要再安装了吧)
> library(R0)
> GTn<-generation.time(type="gamma",val=c(7.5,3.4),step=1)
>  R0EG<-est.R0.EG(data$I,GT=GTn,date.first.obs="2020/07/09")
Waiting for profiling to be done...