[BioC] Export a BigWig with rtracklayer

[Dario Strbenac]

Hello,

I'm having trouble exporting a real-sized BigWig file. It is of hg18 with a score every 20 bases on the 25 real chromosomes. It was created from reading in two different BigWig files, then subtracting their scores :

score(bws[[1]]) <- score(bws[[2]]) - score(bws[[1]])

then

export.bw(bws[[1]], filename, "bedGraph", seqlengths(Hsapiens)[1:25])

After some minutes, I get the error message
Error: serialization is too large to store in a raw vector

I also tried "auto" for dataFormat. If importing then exporting a single BigWig without any modifications to its data, the code works.

What is a better technique ?

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Dario Strbenac
Research Assistant
Cancer Epigenetics
Garvan Institute of Medical Research
Darlinghurst NSW 2010
Australia