假设我有一个清单:
thelist=list(first=data.frame(Year=1:10,Time=rnorm(10)),second=data.frame(Year=1:10,Time=rnorm(10)),third=data.frame(Year=1:10,Time=rnorm(10)))
然后,我想为每个列表元素添加一列,该列的名称不同。
Test=mapply(function(x,y) {
x$y=x$Time+0.5
x=x[complete.cases(x[,3]),][,c(1,3)]
},
x=thelist,y=c("Add1","Add2","Add3")
)
答案是
Test
first second third
Year Integer,10 Integer,10 Integer,10
y Numeric,10 Numeric,10 Numeric,10
这不是我所期望的。我希望答案是:
Test[1:2]
$first
Year Time Add1
1 1 -0.27 Some values...
2 2 0.76
3 3 1.53
4 4 1.00
5 5 -0.25
6 6 0.64
7 7 -0.38
8 8 1.52
9 9 -1.18
10 10 -0.97
$second
Year Time Add2
1 1 0.330 Some values...
2 2 0.075
3 3 1.357
4 4 -1.393
5 5 -0.382
6 6 -0.016
7 7 0.604
8 8 -0.721
9 9 0.665
10 10 -1.115
Update
:
如果我使用SIMPLIFY=FALSE
Test=mapply(function(x,y) {
x$y=x$Time+0.5
x=x[complete.cases(x[,3]),][,c(1,3)]
},
x=thelist,y=c("Add1","Add2","Add3"),SIMPLIFY=FALSE
)
Test[1:2]
$first
Year y
1 1 0.23
2 2 1.26
3 3 2.03
4 4 1.50
5 5 0.25
6 6 1.14
7 7 0.12
8 8 2.02
9 9 -0.68
10 10 -0.47
$second
Year y
1 1 0.83
2 2 0.57
3 3 1.86
4 4 -0.89
5 5 0.12
6 6 0.48
7 7 1.10
8 8 -0.22
9 9 1.16
10 10 -0.62