rsortingxts

how sort in reverse order xts object

I'm trying to do a regular reverse sort, but I don't understand how to do it with an xts object. I want the last date to be in the first line and not the last. I tried several ways but it doesn't work.

library(xts)
x <- rnorm(500) |> cumsum() |> round(1) |> 
                  xts(Sys.time()+1:500) |> to.minutes(name = NULL) 

# dont work :(

# x[nrow(x):1,]
# x[order(index(x),decreasing = T),]
# rev(x)
Solution

  • I think you can't.

    A possible work-around might be:

    xr = as.matrix(x)[rev(seq_len(nrow(x))),,drop=FALSE]
xr
#>                            Open High   Low Close
#> 2024-07-04 16:22:06.941923 -8.8 -5.9  -8.8  -6.6
#> 2024-07-04 16:21:59.941923 -8.0 -3.4 -12.6  -7.8
#> 2024-07-04 16:20:59.941923 -1.7  1.1  -7.7  -7.7
#> 2024-07-04 16:19:59.941923 -4.4  4.9  -5.1  -3.0
#> 2024-07-04 16:18:59.941923  0.1  2.4  -6.5  -5.7
#> 2024-07-04 16:17:59.941923 -1.1  1.4  -9.7  -1.0
#> 2024-07-04 16:16:59.941923  9.9 14.2  -5.4  -1.5
#> 2024-07-04 16:15:59.941923 -2.4 10.8  -4.2   9.5
#> 2024-07-04 16:14:59.941923 -0.6  0.9 -10.4  -2.8
#> 2024-07-04 16:13:59.941923  0.6  1.0  -2.1  -2.1
class(xr)
#> [1] "matrix" "array"

    Data

    suppressMessages(library(xts))
x = rnorm(500) |> cumsum() |> round(1) |> 
  xts(Sys.time()+1:500) |> to.minutes(name = NULL)