[BioC] ERROR: Length of \'group\' must equal number of columns in \'data\'

[aliaselin [guest]]

I'm trying to use edgeR to analyse RNA-seq data following the guidance of "edgeR: differential expression analysis of digital gene expression data".
I have done exactly as the manual told and when tapping the command "d <-
DGEList(counts=d, group=group)", then an error comes as "错误于DGEList(counts = d, group = group) : 
  Length of 'group' must equal number of columns in 'data'
" 

However, length(group) shows that the length of the group is 7, and dim(d) = 37435     7.
So I think they two are equal, so why I got this error?
Many thanks!

 -- output of sessionInfo(): 

R version 2.9.1 (2009-06-26) 
x86_64-redhat-linux-gnu 

locale:
LC_CTYPE=zh_CN.UTF-8;LC_NUMERIC=C;LC_TIME=zh_CN.UTF-8;LC_COLLATE=zh_CN.UTF-8;LC_MONETARY=C;LC_MESSAGES=zh_CN.UTF-8;LC_PAPER=zh_CN.UTF-8;LC_NAME=C;LC_ADDRESS=C;LC_TELEPHONE=C;LC_MEASUREMENT=zh_CN.UTF-8;LC_IDENTIFICATION=C

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] edgeR_1.2.4   Biobase_2.4.1


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