To answer your first question about read.big.matrix(), we don't know what your acc3.dat file is, but it doesn't appear to have been detected as a standard file (like a CSV file) or -- perhaps -- doesn't even exist (or doesn't exist in your current directory)?
Next: > In addition, I am planning to do a multiple imputation with MICE package > using the data read by bigmemory package. > So usually, the multiple imputation code is like this: > imp=mice(data.frame,m=50,seed=1234,print=F) > the data.frame is required. How can I change the big.matrix class > generated by bigmemory package to a data.frame? Please read the help files for bigmemory -- only matrix-like objects are supported. However, the more serious problem is that you can't expect to run just any R function on a big.matrix (or on an ff object, if you check out ff for some nice features). In particular, for large data sets you would likely use up all of RAM (other reasons are more subtle and important, but out of place in this reply). Jay -- John W. Emerson (Jay) Associate Professor of Statistics Department of Statistics Yale University http://www.stat.yale.edu/~jay [[alternative HTML version deleted]] ______________________________________________ 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.
