r - 您将如何对动物园对象列表中的相同列求和？

Question

假设你有:

all.list <- list()
all.list[1] <- list(read.zoo(data.frame(dt=as.Date('2011-01-01')+0:9, a=1:10, b=11:20, c=21:30), index.column = "dt"))
all.list[2] <- list(read.zoo(data.frame(dt=as.Date('2011-01-05')+0:9, a=1:10, b=11:20, c=21:30), index.column = "dt"))
all.list[3] <- list(read.zoo(data.frame(dt=as.Date('2011-01-07')+0:9, a=1:10, b=11:20, c=21:30), index.column = "dt"))

我如何获得一个 zoo 对象，该对象具有列 a、b、c 的每个日期的总和(总和)？

NOTE #1: I would prefer a base-R implementation

Answer 1

使用 merge.zoo 结合 Reduce 的另一种解决方案:

1. 使用每个组件的所有日期的并集来完成列表(缺失值用零填充)
2. 使用 Reduce
对列表项求和

library(zoo)

merged.data <- Reduce("+", do.call(merge, args = c(all.list, retclass = "list", fill = 0)))

## add original column names
setNames(merged.data, names(all.list[[1]]))
#>             a  b  c
#> 2011-01-01  1 11 21
#> 2011-01-02  2 12 22
#> 2011-01-03  3 13 23
#> 2011-01-04  4 14 24
#> 2011-01-05  6 26 46
#> 2011-01-06  8 28 48
#> 2011-01-07 11 41 71
#> 2011-01-08 14 44 74
#> 2011-01-09 17 47 77
#> 2011-01-10 20 50 80
#> 2011-01-11 12 32 52
#> 2011-01-12 14 34 54
#> 2011-01-13 16 36 56
#> 2011-01-14 18 38 58
#> 2011-01-15  9 19 29
#> 2011-01-16 10 20 30

class(merged.data)
#> [1] "zoo"