Hello. I have asked this question in Stack Overflow but the problem is still unsolved. I'm trying to run some R code and it is crashing because of long vector error. I'm running R 3.5.1 on Ubuntu 18.04.1 LTS and getting the following error:

"Error in for (n in 1:k) { : long vectors not supported yet: eval.c:6393"

The input FASTA file size is around 1 GB. The error appears right after running the for loop. I tried to make the input file smaller, but seems this was not the case and I guess could be more related to the used packages. The code that creates the troubles is the following:

library(biomaRt) #version 2.36.1
library(biomartr)#version 0.8.0
library(R.utils) #version 2.7.0
library(seqinr)  #version 3.4.5

genmt <- read.fasta("genymt.fa")

gensize1 <- 16900
subsize1 <- 22*2

BinToDec <- function(x) 
sum(2^(which(rev(unlist(strsplit(x, "")) == 1))-1))

DecToBin <- function(x)
{
 b <- intToBin(x)
 while(nchar(b) < subsize1)
  b <- paste("0",b,sep = "")
b
  }

bin1 <- gsub('A','00',genmt)
bin1 <- gsub('T','01',bin1)
bin1 <- gsub('C','10',bin1)
bin1 <- gsub('G','11',bin1)

for (i in 1:((gensize1*2)-subsize1)) {

 print(i)
 beg1 <- i
 end1 <- i+(subsize1-1)

 sub1 <- substr(bin1, beg1, end1)

 dec1 <- BinToDec(sub1)

 if (i == 1) {
exists1 <- dec1
rep1 <- 1
 } else {
   flag1 <- any(exists1 == dec1)

   if (flag1) {
  ind1 <- which(exists1 == dec1)
  rep1[ind1] <- rep1[ind1]+1
   } else {
   exists1 <- c(exists1,dec1)
   rep1 <- c(rep1,1)
   }
 }
}

dec_res <- -1
k <- 2^subsize1
for (n in 1:k) {
 print(n)
 flag1 <- any(exists1 == n)

 if (!flag1) {
   dec_res <- n
   break
 } 
}

  bin_res <- DecToBin(dec_res)

 gen_res <- matrix(,nrow = 0,ncol = subsize1/2)
ind <- 0
for(i in seq(1,subsize1,2)) {
  ind <- ind + 1
  ifelse(substr(bin_res,i,i+1) == "00",gen_res[ind] <- "A",
        ifelse(substr(bin_res,i,i+1) == "01",gen_res[ind] <- "T",
               ifelse(substr(bin_res,i,i+1) == "10",gen_res[ind] <-"C",gen_res[ind] <- "G")))
  }

As it is clear "K" is large, but it regards to the length of the proposed output. Is there any technical point that I missed or any possible alternative solutions available?

The error message you are seeing is because you're iterating the for-loop over every entry in a vector that is longer than 2^31-1. You can verify that's where the message comes from with the following example:

for(i in 1:(2^44)) { 
    print(i)
}
Error in for (i in 1:(2^44)) { : 
  long vectors not supported yet: eval.c:6387

You can get round this limitation by using a while-loop e.g.

i <- 1
while(i < 2^44) { 
    print(i)
    i <- i+1 
}

However, I'd suggest this is going to take a really long time (> 20 years) to loop through and print every value, so it's probably best to try and find another strategy to approach whatever it is you're doing.

Mike Smith I am trying to run this code on my fastq files:

matrixOfQualities <- as(quals,"matrix") rowSums(matrixOfQualities)[1] In my case [1] is 3725. Please see slide 29 in the link below https://rockefelleruniversity.github.io/Bioconductor_Introduction/presentations/slides/FastQInBioconductor.html#29 But I get an Error Error in asMethod(object) : long vectors not supported yet: memory.c:3888

Can you please help me troubleshoot?>