Hello,

         I am using affy package of Biconductor.I have given raw cel files
as input for normalization. I have to do background correction and
normalization of these files.

I am using the following commands:

> library(affy)
> Data<-ReadAffy()
> est<-rma(Data)
Background correcting
Normalizing
Calculating Expression
Warning message:
package 'hgu133acdf' was built under R version c(2, 0, 0) and help will not
work correctly
Please re-install it
S4'
> write.exprs(est,file="backgroud_corrected")

Till here the raw cel file is being background corrected without any error.

But when i am normalizing the data using quantiles method, using following
command:

> nor<-normalize.AffyBatch.quantiles(Data)

The above command is running without any problem.But when i am trying to
write the normalized file to a new file named"normalized"by the command
given below, it is showing the following error.

> write.exprs(nor,file="normalized")

Error in function (classes, fdef, mtable)  :
  unable to find an inherited method for function "write.exprs", for
signature "AffyBatch"


Please try to solve this problem as early as possible.


With Regards,
Priyanka Jain

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