[R] How to log-2 transform a matrix

[affy snp]

Dear list,

I am wondering how to log-2 based transform a matrix with numeric values?
I tried > CGHlog2<-log2(CGH) but got an error. Then I found for log2(x) in R,
the x has to be a numeric or complex vector. Any method for a matrix?

Thanks a lot and have a good weekend!

Allen


>Error in Math.data.frame(CGH) :
  non-numeric variable in data frame:
WM806SignalAWM1716SignalAWM1862SignalAWM1963SignalAWM1968SignalAWM1976SignalAWM3228SignalAWM3457SignalAWM3061SignalAWM3246SignalAWM3282SignalAWM1931SignalAWM1026SignalAWM3670SignalAWM3702SignalAWM3482SignalAWM3311SignalAWM1960SignalAWM1720SignalAWM3215SignalAWM3451SignalAWM3130SignalAWM2029SignalAWM3243NCI.A5SignalAWM1745SignalAWM3526SignalAWM3682SignalAWM3623SignalAWM3450SignalAWM853.2SignalAWM1930SignalAWM3244NCI.BSignalAWM984SignalAWM3619SignalAWM3297SignalAWM451LuSignalAWM3077SignalAWM3381ASignalAWM3627SignalAWM3218SignalAWM3163SignalAWM3259SignalAWM3506SignalAWM3629SignalAWM3456SignalAWM1346SignalAWM1852SignalARCC13NSignalAJAPOV46NSignalAJAPOV75NSignalAS004285NSignalARCC50NSignalAJAPOV54NSignalAJAPOV92NSignalARCC56NSignalAS004288NSignalAS004295NSignalAS004292NSignalAJAPOV73NSignalAJAPOV52NSignalARCC53NSignalAS004289NSignalARCC25NSignalAS004294NSignalAS004275NSignalAJAPOV32NSignalACN37SignalACN16SignalAS004291NSignalACN17SignalARCC129NS