使用 R 的数据框中基于堆栈的列总和

Question

我现有的数据框看起来如下所示

NAV_Date    NAV    Year  Day       Units   Amount  Balance_Units
2013-06-01  282.5  2013  Saturday  3.540   1000    3.540
2013-06-08  279.3  2013  Saturday  3.581   1000    3.581
2013-06-15  276.0  2013  Saturday  3.623   1000    3.623
2013-06-22  261.6  2013  Saturday  3.822   1000    3.822
2013-06-29  273.3  2013  Saturday  3.659   1000    3.659

我希望我的新数据框有 Balance_Units 列具有如下使用 R 语言给出的条目即余额单位栏应为前值与现值之和这需要在数据框列表上完成

NAV_Date    NAV    Year  Day       Units   Amount  Balance_Units
2013-06-01  282.5  2013  Saturday  3.540   1000    3.540
2013-06-08  279.3  2013  Saturday  3.581   1000    7.121
2013-06-15  276.0  2013  Saturday  3.623   1000    10.744
2013-06-22  261.6  2013  Saturday  3.822   1000    14.566
2013-06-29  273.3  2013  Saturday  3.659   1000    18.225

我试过了，但是没用

 for( i in 1:length(W)) {
  W[[i]]$Units  = 1000/W[[i]]$NAV
  W[[i]]$Amount = 1000
  W[[i]]$Balance_Units = 0
  W[[i]]$Balance_Units = W[[i]]$Units + W[[i]]$Balance_Units
   }

Answer 1

这可以通过 base R

中的一个方便的函数 cumsum 来完成

df1$Balance_Units <- cumsum(df1$Balance_Units)

使用dplyr，可以在mutate

内创建

library(dplyr)
df1 %>%
    mutate(Balance_Units = cumsum(Balance_Units))

如果 'W' 是 data.frame 的 list，我们可以使用 lapply

W <- lapply(W, transform, Balance_Units = cumsum(Balance_Units))

数据

df1 <- structure(list(NAV_Date = c("2013-06-01", "2013-06-08", "2013-06-15", 
"2013-06-22", "2013-06-29"), NAV = c(282.5, 279.3, 276, 261.6, 
273.3), Year = c(2013L, 2013L, 2013L, 2013L, 2013L), Day = c("Saturday", 
"Saturday", "Saturday", "Saturday", "Saturday"), Units = c(3.54, 
3.581, 3.623, 3.822, 3.659), Amount = c(1000L, 1000L, 1000L, 
1000L, 1000L), Balance_Units = c(3.54, 3.581, 3.623, 3.822, 3.659
)), class = "data.frame", row.names = c(NA, -5L))

Answer 2

这是一个 data.table 解决方案。我也为顺序总和添加了一些东西..

library(data.table) 
> dat
     NAV_Date   NAV Year      Day Units Amount Balance_Units
1: 2013-06-01 282.5 2013 Saturday 3.540   1000         3.540
2: 2013-06-08 279.3 2013 Saturday 3.581   1000         3.581
3: 2013-06-15 276.0 2013 Saturday 3.623   1000         3.623
4: 2013-06-22 261.6 2013 Saturday 3.822   1000         3.822
5: 2013-06-29 273.3 2013 Saturday 3.659   1000         3.659

# Cumulative sum
> dat[, cumulative_sum := cumsum(Balance_Units)]
> dat
     NAV_Date   NAV Year      Day Units Amount Balance_Units cumulative_sum
1: 2013-06-01 282.5 2013 Saturday 3.540   1000         3.540          3.540
2: 2013-06-08 279.3 2013 Saturday 3.581   1000         3.581          7.121
3: 2013-06-15 276.0 2013 Saturday 3.623   1000         3.623         10.744
4: 2013-06-22 261.6 2013 Saturday 3.822   1000         3.822         14.566
5: 2013-06-29 273.3 2013 Saturday 3.659   1000         3.659         18.225

# Sequential sum
> dat[, sequential_sum := Balance_Units + shift(x = Balance_Units, fill = 0)]
> dat
     NAV_Date   NAV Year      Day Units Amount Balance_Units cumulative_sum sequential_sum
1: 2013-06-01 282.5 2013 Saturday 3.540   1000         3.540          3.540          3.540
2: 2013-06-08 279.3 2013 Saturday 3.581   1000         3.581          7.121          7.121
3: 2013-06-15 276.0 2013 Saturday 3.623   1000         3.623         10.744          7.204
4: 2013-06-22 261.6 2013 Saturday 3.822   1000         3.822         14.566          7.445
5: 2013-06-29 273.3 2013 Saturday 3.659   1000         3.659         18.225          7.481

使用 R 的数据框中基于堆栈的列总和

Stack Based Column Sum in a data frame using R

r

column-sum

数据