Hi all,
Thank you very much for reading this email. After trying the bigmemory package, I could not figure it out. So I turn to try ff, hopefully someone here have some experience about it? I have a data set (data.frame) with 16459 rows and 457 columns. I am trying to do a multiple imputation for the missing values in the data set. Usually, my ram (4G) is not enough for the imputation with such a big data, so I figured maybe I could try ff. However, I failed again, the ram was still not enough. Here is my code, is there anything wrong with it?
x=ff("acc3",vmode="double",dim=c(16459,457)) # acc3 is the object
name of the data set Warning messages: 1: In as.vmode.default(initdata[1], vmode) : NAs introduced by coercion 2: In as.vmode.default(value, vmode) : NAs introduced by coercion
x=acc3 fix(x) library(mice) # MICE package for multiple imputation for missing value.
Loading required package: MASS Loading required package: nnet Loading required package: lattice mice 2.12 2012-03-25
acc3imp=mice(x,m=50,seed=1234,print=F) # m=50 means data set was
imputed for 50 times, thus, another 50 new # data sets without missing value were generated. Any advice are appreciated. Thank you very much. Best regards, YA ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.