Access xts objects through names stored in a vector

Asked Aug 12 '19 at 01:17

Active Aug 12 '19 at 01:24

Viewed 16 times

I'm not sure why this is difficult or why I can't find the answer to this.

I have multiple 5-column xts objects:

xts1
xts2
xts3

I then have a vector that stores the names of those xts objects:

xtsnames <- c("xts1", "xts2", "xts3")

I want to access and compute the sum of the fourth column in each of those xts objects. When I do:

sum(xts1[4])

it works. But when I do:

sum(xtsnames[1][4])

it doesn't work. I understand why it doesn't work (because xtsnames is a vector of characters), but I couldn't figure out how to do this.

Eventually, it will be in a for loop similar to this:

for (i in 1:length(xtsnames)) {
      fourthcol[,i] <- sum(xtsnames[i][4])
}

edited Aug 12 '19 at 01:24

Ronak Shah

asked Aug 12 '19 at 01:17

Cinji18

you might need `get`, `sum(get(xtsnames[1])[4])` – Ronak Shah Aug 12 '19 at 01:18
Thank you! I don't know that function. – Cinji18 Aug 12 '19 at 01:22
1

If you want to access all of them together you can use `mget` `mget(xtsnames)` which would give you list of `xts` objects. – Ronak Shah Aug 12 '19 at 01:25
1

In fact, saving all of your xts1/2/3, objects as the `list` resulting from `xtslist <- mget(xtsnames)` would be preferential. Then it's simple to access `xtslist[["name"]]` to do analysis. – thelatemail Aug 12 '19 at 01:26

0 Answers0