My existing data frame looks line given below
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
I want my new data frame to have Balance_Units column have entries like given below using R Language i.e Balance unit column should be the sum of previous value and present value This is need to be done on the list of dataframe
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
I tried this but , this is not working
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]]$Balance_Units
}
This can be done with a convenient function cumsum in base R
df1$Balance_Units <- cumsum(df1$Balance_Units)
With dplyr, it can be created within mutate
library(dplyr)
df1 %>%
mutate(Balance_Units = cumsum(Balance_Units))
If 'W' is a list of data.frames, we can use lapply
W <- lapply(W, transform, Balance_Units = cumsum(Balance_Units))
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))