随机数序列和常数

Question

样本数据

set.seed(1)
data=data.frame("id"=c(sort(rep(1:100,3))),
                "survey"=c(rep(1:3,100)))
data$age = ifelse(data$survey == 1, sample(30:60,100,replace=T),0)

目标是为调查等于1的每一行获得一个随机数AGE。然后我想将每个AGE的值3添加为序列。因此，例如，如果调查中的AGE等于1是20，则调查2中的AGE等于23，调查3中的AGE等于26.我在下面显示示例小数据

datasmall = data=data.frame("id"=c(sort(rep(1:4,3))),
                            "survey"=c(rep(1:3,4)),
                            "age"=c(50,53,56,52,55,58,44,47,50,39,42,45))

Answer 1

您只需通过相应的子集添加三个。

set.seed(1)
data$age <- NA  # if column does not yet exist
data$age[data$survey == 1] <- sample(30:60, length(data$age[data$survey == 1]), 
                                     replace=TRUE)
data$age[data$survey == 2] <- data$age[data$survey == 1] + 3
data$age[data$survey == 3] <- data$age[data$survey == 2] + 3

head(data)
#   id survey age
# 1  1      1  38
# 2  1      2  41
# 3  1      3  44
# 4  2      1  41
# 5  2      2  44
# 6  2      3  47