How split vector on chunks with variable size in R?

Question

Let see the example

There is a vector of 100 dates of observations

 x <- 1:100

I would like to split it on chunks related to the percent of original data ("sum" should be "1").

  p <- c(30, 25, 20, 15, 10)
  sum(p)

The "p" is a percent of original data (30% and etc.)

The desired output is chunks of observations with variable size:

 result <- list(list(1:30), list(31:55), list(56:75), list(76:90), list(91:100))

This is useful for parallel processing when the first chunks have bigger size than the next ones.

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akrun · Answer 1 · 2019-05-08T21:41:52.537

0

We can do this with split

result1 <- lapply(unname(split(x, rep(seq_along(p), p))), function(x) list(x))
identical(result, result1)
#[1] TRUE

Or another option with Map

Map(function(x, y) list(x:y), c(1, cumsum(p)[-length(p)]+1), cumsum(p) )

edited May 08 '19 at 21:41

answered May 08 '19 at 19:16

akrun

1 Answers1