Scan Dates will not show

Question

[jmannhei]

Hi All,

I am trying to acquire scan dates so I can obtain batch information to run ComBat. However, when I try to look at the Scan Dates all I get is 'NA'. I have been able to get Scan Dates on other .CEL files with the same code so I am not sure what is going on. Here is my code

filenames<-list.files(path="GDSC CEL Files/",pattern=".CEL")
library(affy)
affy <- ReadAffy(filenames=paste(fdr,filenames,sep=''), phenoData=NULL)


protocol<-affy@protocolData
dates<-protocol@data

Here is an example of the output

> dates
                               ScanDate
5500024030401071707289.A01.CEL     <NA>
5500024030401071707289.A02.CEL     <NA>
5500024030401071707289.A03.CEL     <NA>
5500024030401071707289.A04.CEL     <NA>
5500024030401071707289.A05.CEL     <NA>
5500024030401071707289.A06.CEL     <NA>
5500024030401071707289.A07.CEL     <NA>
5500024030401071707289.A08.CEL     <NA>
5500024030401071707289.A09.CEL     <NA>
5500024030401071707289.A10.CEL     <NA>
5500024030401071707289.A11.CEL     <NA>
5500024030401071707289.A12.CEL     <NA>

Any help or info would be extremely helpful. Thanks !