如何在 tibble 的每个元素上应用 "complicated" 用户定义的函数

Question

我到处寻找这个（看似简单的）问题的答案，但一无所获所以我希望有人能帮助我或指出正确的方向。

我有一个相当复杂的子模型，我想将其应用到数据集，但如果我只是使用 use mutate，我会收到一个错误 Variables must be length 1 or 21. 添加 rowwise() 似乎不会影响它。

让我使用以下愚蠢的问题说明：

myData <- tibble(x=10:20, y=c("a", "b","a", "b","a", "b","a", "b","a", "b","a"))

staticData <- tibble(x=0:100, y=c("a"),f=x/100) %>% union (tibble(x=0:100, y=c("b"),f=x/1000))

ComplicatedFunction <- function(mystaticData, myx, myy) {
  #make the base table 
  myBaseTable <- tibble(
    y = myy,
    x = c(myx:(myx + 20)) 
  )
  #add  f rates
  myBaseTable <- left_join(myBaseTable,mystaticData)
  #add stuff
  myBaseTable <- myBaseTable %>% 
    mutate(z = 1 - (f * 0.8)) %>% 
    mutate(zCumulative = cumprod(z)) 
  #Calculate the thing
  myCalculatedThing <- sum(myBaseTable$zCumulative)

  return(myCalculatedThing)
}

#This is what I want to do 
myData %>% mutate(newcol = ComplicatedFunction(mystaticData = staticData, 
                                               myx = x, 
                                               myy = y))
#this works
ComplicatedFunction(mystaticData = staticData, 
                    myx = 19, 
                    myy = "b")
ComplicatedFunction(mystaticData = staticData, 
                    myx = 20, 
                    myy = "a")

#This works (but would be silly as I want the function to be evaluated for each line)
myData %>% mutate(newcol = ComplicatedFunction(mystaticData = staticData, 
                                               myx = 15, 
                                               myy = "a"))

#This no longer works, but I dont understand what I am doing wrong
myData %>% mutate(newcol = ComplicatedFunction(mystaticData = staticData, 
                                               myx = x, 
                                               myy = "a"))

#I tried rowwise(), but this doesnt seem to work either 
myData %>% rowwise() %>% mutate(newcol = ComplicatedFunction(mystaticData = staticData, 
                                               myx = x, 
                                               myy = y))

我希望有人能给我解释一下我做错了什么。

非常感谢！

西尔万

Answer 1

您可以通过使用 partial:

创建一个新函数来实现

library(purrr)
newCF <- partial(ComplicatedFunction, mystaticData = staticData)
myData %>% rowwise() %>% mutate(newcol = newCF(myx = x, 
                                           myy = y))

如何在 tibble 的每个元素上应用 "complicated" 用户定义的函数

How to apply a "complicated" user defined function on each element of a tibble

r

function

dplyr

tibble