[BioC] limma package : Error in sigToEnv(signature, fdef) : Trying to ge t slot "signature" from an object of a basic class ("NULL") with no slots

[James W. MacDonald]

He, Yiwen (NIH/CIT) wrote:
> Hi, I was using an older (11/23/04) version of limma package and it worked
> fine for my log ratio data. I just installed the latest version (2/24/05)
> but got this error message when I did:
> 
>  
> 
> 
>>lmFit(data)                  # data is just a matrix of log ratios.
> 
> 
>  
> 
> Error in sigToEnv(signature, fdef) : Trying to get slot "signature" from an
> object of a basic class ("NULL") with no slots

My bet is that data (bad variable name, btw; you are masking an existing 
R function) is not a matrix, but a data.frame. Try

lmFit(as.matrix(data))

HTH,

Jim



-- 
James W. MacDonald
Affymetrix and cDNA Microarray Core
University of Michigan Cancer Center
1500 E. Medical Center Drive
7410 CCGC
Ann Arbor MI 48109
734-647-5623