R语言,请问怎么在数据框新增一列为前两列之比?答:Weight<-c(4.17, 5.58, 5.18, 6.11, 4.5, 4.61, 5.17, 4.53, 5.33, 5.14);Height<-c(1.75, 1.8, 1.65, 1.9, 1.74, 1.91, 1.75, 1.8, 1.65, 1.9);save1<-data.frame(Weight,Height);//身高体重数据写入文本文件 write.csv(save1, file = "foo1.csv",...
如何在R语言中计算C-index答:library(survival)library(Hmisc)age <- rnorm(200, 50, 10)bp <- rnorm(200,120, 15)d.time <- rexp(200)cens <- runif(200,.5,2)death <- d.time <= cens os <- pmin(d.time, cens)sample.data <- data.frame(age = age,bp = bp,os = os,death = death)让我们...