Convert RAW data from TXT to CEL format in ArrayExpress

The raw data of some datasets in ArrayExpress are in TXT format. Although some of them are from Affymetrix platform, they cann't be loaded by default using R packages like affyio.

After checking the definition of CEL format here(http://dept.stat.lsa.umich.edu/~kshedden/Courses/Stat545/Notes/AffxFileFormats/cel.html), we can find that the v3 CEL format is simple.  We can write a script to convert the TXT files into CEL files.

I put the example for Arabidopsis Affymetrix microarray ATH1 here. This script can be easily changed to work for other Affymetrix chips.

ArrayExpress_Raw2CEL.pl