r - 如何从 R 中的数据框中去除美元符号 ($)？

Question

我是 R 的新手，正在为看似极其简单的查询而苦苦挣扎。

我已经使用 read.csv 将一个 csv 文件导入到 R 中，并试图在整理数据和进一步分析之前删除美元符号($)(美元符号对图表造成严重破坏)。

我一直在尝试使用 dplyr 和 gsub 从数据框中去除 $，但没有成功，我非常感谢有关如何去做的一些建议。

我的数据框是这样的:

> str(data)
 'data.frame':  50 obs. of  17 variables:
 $ Year            : int  1 2 3 4 5 6 7 8 9 10 ...
 $ Prog.Cost       : Factor w/ 2 levels "-$3,333","$0": 1 2 2 2 2 2 2 2 2 2 ...
 $ Total.Benefits  : Factor w/ 44 levels "$2,155","$2,418",..: 25 5 7 11 12 10 9 14 13 8 ...
 $ Net.Cash.Flow   : Factor w/ 45 levels "-$2,825","$2,155",..: 1 6 8 12 13 11 10 15 14 9 ...
 $ Participant     : Factor w/ 46 levels "$0","$109","$123",..: 1 1 1 45 46 2 3 4 5 6 ...
 $ Taxpayer        : Factor w/ 48 levels "$113","$114",..: 19 32 35 37 38 40 41 45 48 47 ...
 $ Others          : Factor w/ 47 levels "-$9","$1,026",..: 12 25 26 24 23 11 9 10 8 7 ...
 $ Indirect        : Factor w/ 42 levels "-$1,626","-$2",..: 1 6 10 18 22 24 28 33 36 35 ...
 $ Crime           : Factor w/ 35 levels "$0","$1","$10",..: 6 11 13 19 21 23 28 31 33 32 ...
 $ Child.Welfare   : Factor w/ 1 level "$0": 1 1 1 1 1 1 1 1 1 1 ...
 $ Education       : Factor w/ 1 level "$0": 1 1 1 1 1 1 1 1 1 1 ...
 $ Health.Care     : Factor w/ 38 levels "-$10","-$11",..: 7 7 7 7 2 8 12 36 30 9 ...
 $ Welfare         : Factor w/ 1 level "$0": 1 1 1 1 1 1 1 1 1 1 ...
 $ Earnings        : Factor w/ 41 levels "$0","$101","$104",..: 1 1 1 22 23 24 25 26 27 28 ...
 $ State.Benefits  : Factor w/ 37 levels "$102","$117",..: 37 1 3 4 6 10 12 18 24 27 ...
 $ Local.Benefits  : Factor w/ 24 levels "$115","$136",..: 24 1 2 12 14 16 19 22 23 21 ...
 $ Federal.Benefits: Factor w/ 39 levels "$0","$100","$102",..: 1 1 1 12 12 17 20 19 19 21 ...

Answer 1

如果您只需要删除$ 并且不想更改列的class。

indx <- sapply(data, is.factor) 
data[indx] <- lapply(data[indx], function(x) 
                            as.factor(gsub("\\$", "", x)))

如果您需要 numeric 列，您也可以去掉 ,(由@David 提供 Arenburg) 并通过 as.numeric

转换为 numeric

data[indx] <- lapply(data[indx], function(x) as.numeric(gsub("[,$]", "", x)))

你可以把它包装在一个函数里

f1 <- function(dat, pat="[$]", Class="factor"){
  indx <- sapply(dat, is.factor)
  if(Class=="factor"){
  dat[indx] <- lapply(dat[indx], function(x) as.factor(gsub(pat, "", x)))
     }
  else {
  dat[indx] <- lapply(dat[indx], function(x) as.numeric(gsub(pat, "", x)))
   }
  dat
 }

 f1(data)
 f1(data, pat="[,$]", "numeric")

数据

set.seed(24)
data <- data.frame(Year=1:6, Prog.Cost= sample(c("-$3,3333", "$0"),
          6, replace=TRUE), Total.Benefits= sample(c("$2,155","$2,418",
         "$2,312"), 6, replace=TRUE))