[BioC] Error in normalisation routines

[Dion Whitehead]

Hi all,

I am getting this frustrating error in the 'affy' package, using the 
'justMAS' function.  I have looked at the function but cannot figure out 
where the error comes from of how to fix it.

x <- justMAS(cold.root.00.5.raw, tgt=100)

Background correcting
Retrieving data from AffyBatch...done.
Computing expression calls...
....done.
scaling to a TGT of 100 ...Scale factor for: COLD_30MIN_ROOT_REP1.cel 
0.337464082097439
Scale factor for: COLD_30MIN_ROOT_REP2.cel 0.402367050097728
Scale factor for: CONTROL_30MIN_ROOT_REP1.cel 0.342672641420889
Scale factor for: CONTROL_30MIN_ROOT_REP2.cel 0.341954877809006
Error in sigToEnv(signature, fdef) : Trying to get slot "signature" from 
an object of a basic class ("NULL") with no slots

Anyone have any ideas?

Dion

-- 
***************************
Dion Whitehead
Division of Bioinformatics
The Westfalian Wilhelms University of Muenster
Botanical Institute, Schlossplatz 4
D48149 Muenster
Germany

Phone: +49-251-83-21633
Fax:   +49-251-83-21631
http://www.uni-muenster.de/Biologie.Botanik/ebb/