突变数据框中的多个列

时间:2014-10-06 15:24:21

标签: r dplyr stata

我有一个看起来像这样的数据集。

bankname    bankid  year    totass  cash    bond    loans
Bank A      1       1881    244789  7250    20218   29513
Bank B      2       1881    195755  10243   185151  2800
Bank C      3       1881    107736  13357   177612  NA
Bank D      4       1881    170600  35000   20000   5000
Bank E      5       1881    3200000 351266  314012  NA

我想根据银行资产负债表计算一些比率。我希望数据集看起来像这样

bankname    bankid  year    totass  cash    bond    loans   CashtoAsset BondtoAsset LoanstoAsset
Bank A      1       1881    2447890 7250    202100  951300  0.002   0.082   0.388
Bank B      2       1881    195755  10243   185151  2800    0.052   0.945   0.014
Bank C      3       1881    107736  13357   177612  NA  0.123   1.648585431 NA
Bank D      4       1881    170600  35000   20000   5000    0.205   0.117   0.029
Bank E      5       1881    32000000    351266  314012  NA  0.0109  0.009   NA

以下是复制数据的代码

bankname <- c("Bank A","Bank B","Bank C","Bank D","Bank E")
bankid <- c( 1, 2,  3,  4,  5)
year<- c( 1881, 1881,   1881,   1881,   1881)
totass  <- c(244789,    195755, 107736, 170600, 32000000)
cash<-c(7250,10243,13357,35000,351266)
bond<-c(20218,185151,177612,20000,314012)
loans<-c(29513,2800,NA,5000,NA)
bankdata<-data.frame(bankname, bankid,year,totass, cash, bond, loans)

首先,我在资产负债表中删除了NAs。

cols <- c("totass", "cash", "bond", "loans")
bankdata[cols][is.na(bankdata[cols])] <- 0

然后我计算比率

library(dplyr)
bankdata<-mutate(bankdata,CashtoAsset = cash/totass)
bankdata<-mutate(bankdata,BondtoAsset = bond/totass)
bankdata<-mutate(bankdata,loanstoAsset =loans/totass)

但是,我不是一行一行地计算所有这些比率,而是想要一次性创建这样做。在Stata,我会做

foreach x of varlist cash bond loans {
by bankid: gen `x'toAsset = `x'/ totass
}

我该怎么做?

6 个答案:

答案 0 :(得分:36)

更新(截至2019年3月18日)

发生了变化。我们一直在funs().funs)中使用funs(name = f(.)。但这已经改变了(dplyr 0.8.0以上)。现在我们使用funslist)代替list(name = ~f(.))。请参阅以下新示例。

bankdata %>%
mutate_at(.funs = list(toAsset = ~./totass), .vars = vars(cash:loans))

bankdata %>%
mutate_at(.funs = list(toAsset = ~./totass), .vars = c("cash", "bond", "loans"))

bankdata %>%
mutate_at(.funs = list(toAsset = ~./totass), .vars = 5:7)

更新(截至2017年12月2日)

由于我回答了这个问题,我意识到有些SO用户一直在检查这个问题。从那以后,dplyr包已经改变了。因此,我留下以下更新。我希望这可以帮助一些R用户学习如何使用mutate_at()

mutate_each()现已弃用。您想要使用mutate_at()。您可以在.vars中指定要应用功能的列。一种方法是使用vars()。另一种方法是使用包含列名的字符向量,您希望在.fun中应用自定义函数。另一种是指定带有数字的列(例如,在这种情况下为5:7)。请注意,如果您使用group_by()列,则需要更改列位置的数量。看看this question

bankdata %>%
mutate_at(.funs = funs(toAsset = ./totass), .vars = vars(cash:loans))

bankdata %>%
mutate_at(.funs = funs(toAsset = ./totass), .vars = c("cash", "bond", "loans"))

bankdata %>%
mutate_at(.funs = funs(toAsset = ./totass), .vars = 5:7)

#  bankname bankid year   totass   cash   bond loans cash_toAsset bond_toAsset loans_toAsset
#1   Bank A      1 1881   244789   7250  20218 29513   0.02961734  0.082593581    0.12056506
#2   Bank B      2 1881   195755  10243 185151  2800   0.05232561  0.945830247    0.01430359
#3   Bank C      3 1881   107736  13357 177612    NA   0.12397899  1.648585431            NA
#4   Bank D      4 1881   170600  35000  20000  5000   0.20515826  0.117233294    0.02930832
#5   Bank E      5 1881 32000000 351266 314012    NA   0.01097706  0.009812875            NA

我故意将toAsset提供给.fun中的自定义函数,因为这有助于我安排新的列名。以前,我使用rename()。但我认为在目前的方法中使用gsub()清理列名要容易得多。如果上述结果保存为out,您需要运行以下代码才能删除列名称中的_

names(out) <- gsub(names(out), pattern = "_", replacement = "")

原始答案

我认为你可以使用dplyr以这种方式保存一些输入。缺点是你要覆盖现金,债券和贷款。

bankdata %>%
    group_by(bankname) %>%
    mutate_each(funs(whatever = ./totass), cash:loans)

#  bankname bankid year   totass       cash        bond      loans
#1   Bank A      1 1881   244789 0.02961734 0.082593581 0.12056506
#2   Bank B      2 1881   195755 0.05232561 0.945830247 0.01430359
#3   Bank C      3 1881   107736 0.12397899 1.648585431         NA
#4   Bank D      4 1881   170600 0.20515826 0.117233294 0.02930832
#5   Bank E      5 1881 32000000 0.01097706 0.009812875         NA

如果您更喜欢预期的结果,我认为有必要打字。重命名部分似乎是你必须做的事情。

bankdata %>%
    group_by(bankname) %>%
    summarise_each(funs(whatever = ./totass), cash:loans) %>%
    rename(cashtoAsset = cash, bondtoAsset = bond, loanstoAsset = loans) -> ana;
    ana %>%
    merge(bankdata,., by = "bankname")

#  bankname bankid year   totass   cash   bond loans cashtoAsset bondtoAsset loanstoAsset
#1   Bank A      1 1881   244789   7250  20218 29513  0.02961734 0.082593581   0.12056506
#2   Bank B      2 1881   195755  10243 185151  2800  0.05232561 0.945830247   0.01430359
#3   Bank C      3 1881   107736  13357 177612    NA  0.12397899 1.648585431           NA
#4   Bank D      4 1881   170600  35000  20000  5000  0.20515826 0.117233294   0.02930832
#5   Bank E      5 1881 32000000 351266 314012    NA  0.01097706 0.009812875           NA

答案 1 :(得分:3)

Applycbind

cbind(bankdata,apply(bankdata[,5:7],2, function(x) x/bankdata$totass))
names(bankdata)[8:10] <- paste0(names(bankdata)[5:7], 'toAssest’)

> bankdata
  bankname bankid year   totass   cash   bond loans cashtoAssest bondtoAssest loanstoAssest
1   Bank A      1 1881   244789   7250  20218 29513   0.02961734  0.082593581    0.12056506
2   Bank B      2 1881   195755  10243 185151  2800   0.05232561  0.945830247    0.01430359
3   Bank C      3 1881   107736  13357 177612    NA   0.12397899  1.648585431            NA
4   Bank D      4 1881   170600  35000  20000  5000   0.20515826  0.117233294    0.02930832
5   Bank E      5 1881 32000000 351266 314012    NA   0.01097706  0.009812875            NA

答案 2 :(得分:2)

这是一个data.table解决方案。

library(data.table)
setDT(bankdata)
bankdata[, paste0(names(bankdata)[5:7], "toAsset") := 
           lapply(.SD, function(x) x/totass), .SDcols=5:7]
bankdata
#    bankname bankid year   totass   cash   bond loans cashtoAsset bondtoAsset loanstoAsset
# 1:   Bank A      1 1881   244789   7250  20218 29513  0.02961734 0.082593581   0.12056506
# 2:   Bank B      2 1881   195755  10243 185151  2800  0.05232561 0.945830247   0.01430359
# 3:   Bank C      3 1881   107736  13357 177612     0  0.12397899 1.648585431   0.00000000
# 4:   Bank D      4 1881   170600  35000  20000  5000  0.20515826 0.117233294   0.02930832
# 5:   Bank E      5 1881 32000000 351266 314012     0  0.01097706 0.009812875   0.00000000

答案 3 :(得分:1)

这是dplyr的一个重大缺点:就我所知,没有直接的方式以编程方式使用它而不是交互式地使用它没有某种&#34; hack&#34 ;喜欢可悲的eval(parse(text=foo))成语。

最简单的方法与Stata方法相同,但字符串操作在R中比在Stata(或任何其他脚本语言中)更为冗长。

for (x in c("cash", "bond", "loans")) {
  bankdata[sprintf("%stoAsset", x)] <- bankdata[x] / bankdata$totass  # or, equivalently, bankdata["totass"] for a consistent "look"
  ## can also replace `sprintf("%stoAsset", x)` with `paste0(c(x, "toAsset"))` or even `paste(x, "toAsset", collapse="") depending on what makes more sense to you.
}

为了使整个事物更像Stata,你可以像within一样包装整个事物:

bankdata <- within(bankdata, for (x in c("cash", "bond", "loans")) {
  assign(x, get(x) / totass)
})

但这需要对getassign函数进行一些黑客攻击,这些函数一般不会安全使用,尽管在您的情况下它可能不是什么大问题。例如,我不推荐使用dplyr尝试类似的技巧,因为dplyr滥用了R的非标准评估功能,而且它可能比它更麻烦价值。要获得速度更快且可能更高级的解决方案,请查看data.table包(我认为)允许您使用类似Stata的循环语法,但使用dplyr - 就像速度一样。查看CRAN上的包装插图。

另外,你真的,确定要将NA条目重新分配给0吗?

答案 4 :(得分:0)

你可能会比必要时更难。试试看,看看它是否能满足您的需求。

bankdata$CashtoAsset <- bankdata$cash / bankdata$totass
bankdata$BondtoAsset <- bankdata$bond / bankdata$totass
bankdata$loantoAsset <- bankdata$loans / bankdata$totass
bankdata

产生这个:

bankname bankid year   totass   cash   bond loans CashtoAsset BondtoAsset loantoAsset 
1   Bank A      1 1881   244789   7250  20218 29513  0.02961734 0.082593581  0.12056506 
2   Bank B      2 1881   195755  10243 185151  2800  0.05232561 0.945830247  0.01430359 
3   Bank C      3 1881   107736  13357 177612     0  0.12397899 1.648585431  0.00000 
4   Bank D      4 1881   170600  35000  20000  5000  0.20515826 0.117233294  0.02930832 
5   Bank E      5 1881 32000000 351266 314012     0  0.01097706 0.009812875  0.00000000

这应该让你开始朝着正确的方向前进。

答案 5 :(得分:0)

尝试:

for(i in 5:7){
     bankdata[,(i+3)] = bankdata[,i]/bankdata[,4]
}
names(bankdata)[(5:7)+3] =  paste0(names(bankdata)[5:7], 'toAssest')

输出:

bankdata
  bankname bankid year   totass   cash   bond loans cashtoAssest bondtoAssest loanstoAssest
1   Bank A      1 1881   244789   7250  20218 29513   0.02961734  0.082593581    0.12056506
2   Bank B      2 1881   195755  10243 185151  2800   0.05232561  0.945830247    0.01430359
3   Bank C      3 1881   107736  13357 177612     0   0.12397899  1.648585431    0.00000000
4   Bank D      4 1881   170600  35000  20000  5000   0.20515826  0.117233294    0.02930832
5   Bank E      5 1881 32000000 351266 314012     0   0.01097706  0.009812875    0.00000000