声明列名的函数

Question

我有一个用 R 编写的函数。基本上我是根据其值将函数应用于数据框列。谁能帮帮我？................................

asd <- data.frame(a = c("High Impact", "High Impact", "Medium Impact"),
                  b = c("High Impact", "No Impact", "High Impact"),
                  c = c("Low Impact", "No Impact", "Medium Impact"))

final_score <- function(q1,q2,q3){
  # ifelse(c == "A", "Low", "High")
  if (q1 == "Not Applicable") {
    q1_value = 0
  } else if (q1 == "No Impact") {
    q1_value = 0
  } else if (q1 == "Low Impact") {
    q1_value = 1
  } else if (q1 == "Medium Impact") {
    q1_value = 2
  } else if (q1 == "High Impact") {
    q1_value = 3
  }
  
  if (q2 == "Not Applicable") {
    q2_value = 0
  } else if (q2 == "No Impact") {
    q2_value = 0
  } else if (q2 == "Low Impact") {
    q2_value = 1
  } else if (q2 == "Medium Impact") {
    q2_value = 2
  } else if (q2 == "High Impact") {
    q2_value = 3
  }
  
  if (q3 == "Not Applicable") {
    q3_value = 0
  } else if (q3 == "No Impact") {
    q3_value = 0
  } else if (q3 == "Low Impact") {
    q3_value = 1
  } else if (q3 == "Medium Impact") {
    q3_value = 2
  } else if (q3 == "High Impact") {
    q3_value = 3
  }
  fs  = q1_value + q2_value + q3_value
  return(fs)
}

###Expected output
asd$new <- final_score(asd$a,asd$b,asd$c)
              a           b             c       new
1   High Impact High Impact    Low Impact       7
2   High Impact   No Impact     No Impact       3
3 Medium Impact High Impact Medium Impact       7

我有一个用 R 编写的函数。基本上我是根据其值将函数应用于数据框列。谁能帮帮我？................................

Answer 1

当您发现自己一遍又一遍地复制代码时，请考虑循环还是函数是更好的答案。这是一个在没有额外包的情况下进行计算的提议。但是，使用合适的包可以更简单地完成重新编码。 car 中的 recode 功能只是众多建议中的一个。

# Your example data
asd <- data.frame(a = c("High Impact", "High Impact", "Medium Impact"),
                  b = c("High Impact", "No Impact", "High Impact"),
                  c = c("Low Impact", "No Impact", "Medium Impact"))


# a small function for one value:
score <- function(value){
  if (value == "Not Applicable") return(0)
  if (value == "No Impact") return(0)
  if (value == "Low Impact") return(1)
  if (value == "Medium Impact") return(2)
  if (value == "High Impact") return(3)
  return(NA)
}

# apply that small function to each value in asd

apply(asd, 1:2, score)

# rowSums are the sums of the rows...

asd$new <- rowSums(apply(asd, 1:2, score))

print(asd)

Answer 2

在dplyr中你可以使用case_when和across-

library(dplyr)

asd %>%
  mutate(new = rowSums(across(.fns = ~case_when(. %in% c("Not Applicable", "No Impact") ~ 0, 
                                  . =="Low Impact" ~ 1, 
                                  . == "Medium Impact" ~ 2, 
                                  . == "High Impact" ~ 3))))

#              a           b             c new
#1   High Impact High Impact    Low Impact   7
#2   High Impact   No Impact     No Impact   3
#3 Medium Impact High Impact Medium Impact   7

Answer 3

基本 R 选项

asd$new <- rowSums(
  `dim<-`(
    as.integer(factor(
      as.matrix(asd),
      levels = c("Low Impact", "Medium Impact", "High Impact")
    )),
    dim(asd)
  ),
  na.rm = TRUE
)

给予

> asd
              a           b             c new
1   High Impact High Impact    Low Impact   7
2   High Impact   No Impact     No Impact   3
3 Medium Impact High Impact Medium Impact   7

声明列名的函数

function declaring column names

r

dataframe

recode