R将月份名称与字符串合并

Question

我想把每个月的名字和三个字符串结合起来：'min'，'max'，‘min’

我试过这个：

paste(month.name,rep(c('min','max','mean'),12))

但是，代替“一月的分钟”，“一月的最大值”，“一月的意思”，我搞错了“一月分”“二月最大”“三月”的意思.

你有什么意见建议？谢谢

沼气

Answer 1

将rep放在几个月左右，并指定要在each = 3中重复3次

paste(rep(month.name, each = 3), c("min","max","mean"))

# [1] "January min"    "January max"    "January mean"   "February min"  
# [5] "February max"   "February mean"  "March min"      "March max" 
# etc

Answer 2

保持简单;-)

month <- c("January", "February", "March")
value <- c("min", "max", "mean")
outer(month, value, paste)

     [,1]           [,2]           [,3]           
[1,] "January min"  "January max"  "January mean" 
[2,] "February min" "February max" "February mean"
[3,] "March min"    "March max"    "March mean"  

若要以向量形式获取它，请使用c()

c(outer(month, value, paste))

[1] "January min"   "February min"  "March min"     "January max"  
[5] "February max"  "March max"     "January mean"  "February mean"
[9] "March mean"   

c(t(outer(month, value, paste)))

[1] "January min"   "January max"   "January mean"  "February min" 
[5] "February max"  "February mean" "March min"     "March max"    
[9] "March mean"   

Answer 3

我们可以循环将像paste这样的矢量化函数应用到months向量上。

library(purrr)

month <- c("January", "February", "March")
value <- c("min", "max", "mean")

map(month, ~paste(.x, value, sep = ' ')) %>%
        unlist

[1] "January min"   "January max"   "January mean"  "February min"  "February max"  "February mean"
[7] "March min"     "March max"     "March mean"