If I have vectors m1, m2, ... m"n" and I want to create a vector that includes all of the values, how would I go about this?
For example:
m1 = c(0, 2, 4)
m2 = c(1, 4)
m3 = (3)
I want a vector "totalmods" which outputs {0, 2, 4, 1, 4, 3}
My attempt where nummod is "n", the vector with the largest number was:
for(i in 1:nummod){
totalmods <- c(paste("m",i, sep = ""))
}
Thanks for your help!
You can use mget and unlist
unlist(mget(ls(pattern = "^m\\d+$")), use.names = FALSE)
# [1] 0 2 4 1 4 3
We create a list with all objects whose names start with "m" (^m) and end with one or more digit (\\d+$). We use unlist to create a vector.
A user asked for a benchmark in the comments (and I became curious)
x <- 2:2000
y <- setNames(lapply(x, seq_len), paste0("m", x))
library(microbenchmark)
microbenchmark(markus = unlist(y, use.names = FALSE),
tmfmnk = Reduce(c, y),
akrun = purrr::flatten_dbl(y)
times = 10L)
#Unit: milliseconds
# expr min lq mean median uq max neval
# markus 13.7329 13.8566 22.09223 13.9139 14.1638 75.9402 10
# tmfmnk 3427.3571 3614.2938 3761.36990 3806.0890 3928.1482 4004.7853 10
# akrun 42.7355 64.4865 153.8598 148.5418 240.0674 286.8956 10
An option with flatten
library(purrr)
mget(ls(pattern = "^m\\d+")) %>%
flatten_dbl
#[1] 0 2 4 1 4 3