Extract rows from a data.frame based on common values with a list

Question

I'm looking for an easy way for filtering rows from a data.frame, based on a list of numeric sequences.

Here's a exemple:

My initial data frame:

data <- data.frame(x=c(0,1,2,0,1,2,3,4,5,12,2,0,10,11,12,13),y="other_data")

My list:

list1 <- list(1:5,10:13)

My goal is to keep only the rows from "data" which contains exactly the same numeric sequences of "list1" as in the "x" column of "data". So the output data.frame should be:

finaldata <- data.frame(x=c(1:5,10:13),y="other_data")

Any ideas for doing this?

Answer 1

I started with a custom function to get the subset for one sequence, then it's easy to extend with lapply.

#function that takes sequence and a vector
#and returns indices of vector that have complete sequence
get_row_indices<- function(sequence,v){
  #get run lengths of whether vector is in sequence
  rle_d <- rle(v %in% sequence)
  #test if it's complete, so both v in sequence and length of 
  #matches is length of sequence
  select <- rep(length(sequence)==rle_d$lengths &rle_d$values,rle_d$lengths)

  return(select)

}


#add row ID to data to show selection
data$row_id <- 1:nrow(data)
res <- do.call(rbind,lapply(list1,function(x){
  return(data[get_row_indices(sequence=x,v=data$x),])
}))

res

> res
    x          y row_id
5   1 other_data      5
6   2 other_data      6
7   3 other_data      7
8   4 other_data      8
9   5 other_data      9
13 10 other_data     13
14 11 other_data     14
15 12 other_data     15
16 13 other_data     16